The serotonin 1A receptor (or 5-HT
1A receptor) is a subtype of
serotonin receptor, or 5-HT receptor, that binds
serotonin, also known as 5-HT, a
neurotransmitter. 5-HT1A is expressed in the
brain
A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a ve ...
,
spleen
The spleen is an organ found in almost all vertebrates. Similar in structure to a large lymph node, it acts primarily as a blood filter. The word spleen comes . , and neonatal
kidney
The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blo ...
. It is a
G protein-coupled receptor
G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of evolutionarily-related p ...
(GPCR), coupled to the
Gi protein, and its activation in the brain mediates hyperpolarisation and reduction of firing rate of the postsynaptic neuron. In humans, the serotonin 1A receptor is encoded by the HTR1A
gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
.
Distribution
The 5-HT
1A receptor is the most widespread of all the 5-HT receptors. In the
central nervous system
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all p ...
, 5-HT
1A receptors exist in the
cerebral cortex
The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. The cerebral cortex mostly consists of the six-layered neocortex, with just 10% consistin ...
,
hippocampus
The hippocampus (via Latin from Greek , ' seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, ...
,
septum,
amygdala
The amygdala (; plural: amygdalae or amygdalas; also '; Latin from Greek, , ', 'almond', 'tonsil') is one of two almond-shaped clusters of nuclei located deep and medially within the temporal lobes of the brain's cerebrum in complex verte ...
, and
raphe nucleus in high densities, while low amounts also exist in the
basal ganglia
The basal ganglia (BG), or basal nuclei, are a group of subcortical nuclei, of varied origin, in the brains of vertebrates. In humans, and some primates, there are some differences, mainly in the division of the globus pallidus into an exter ...
and
thalamus
The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, ...
.
The 5-HT
1A receptors in the raphe nucleus are largely
somatodendritic autoreceptor
An autoreceptor is a type of receptor located in the membranes of nerve cells. It serves as part of a negative feedback loop in signal transduction. It is only sensitive to the neurotransmitters or hormones released by the neuron on which the au ...
s, whereas those in other areas such as the hippocampus are
postsynaptic
Chemical synapses are biological junctions through which neurons' signals can be sent to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous sys ...
receptors.
Function
Neuromodulation
5-HT
1A receptor
Receptor may refer to:
* Sensory receptor, in physiology, any structure which, on receiving environmental stimuli, produces an informative nerve impulse
*Receptor (biochemistry), in biochemistry, a protein molecule that receives and responds to a ...
agonists are involved in
neuromodulation
Neuromodulation is the physiological process by which a given neuron uses one or more chemicals to regulate diverse populations of neurons. Neuromodulators typically bind to metabotropic, G-protein coupled receptors (GPCRs) to initiate a second ...
. They decrease
blood pressure and
heart rate
Heart rate (or pulse rate) is the frequency of the heartbeat measured by the number of contractions (beats) of the heart per minute (bpm). The heart rate can vary according to the body's physical needs, including the need to absorb oxygen and excr ...
via a central mechanism, by inducing peripheral
vasodilation
Vasodilation is the widening of blood vessels. It results from relaxation of smooth muscle cells within the vessel walls, in particular in the large veins, large arteries, and smaller arterioles. The process is the opposite of vasoconstrictio ...
, and by stimulating the
vagus nerve
The vagus nerve, also known as the tenth cranial nerve, cranial nerve X, or simply CN X, is a cranial nerve that interfaces with the parasympathetic control of the heart, lungs, and digestive tract. It comprises two nerves—the left and righ ...
.
These effects are the result of activation of 5-HT
1A receptors within the
rostral ventrolateral medulla
The rostral ventrolateral medulla (RVLM), also known as the pressor area of the medulla, is a brain region that is responsible for basal and reflex control of sympathetic activity associated with cardiovascular function. Abnormally elevated sympa ...
.
The
sympatholytic antihypertensive
Antihypertensives are a class of drugs that are used to treat hypertension (high blood pressure). Antihypertensive therapy seeks to prevent the complications of high blood pressure, such as stroke and myocardial infarction. Evidence suggests tha ...
drug urapidil
Urapidil is a sympatholytic antihypertensive drug. It acts as an α1-adrenoceptor antagonist and as an 5-HT1A receptor agonist. Although an initial report suggested that urapidil was also an α2-adrenoceptor agonist, this was not substantiated ...
is an
α1-adrenergic receptor antagonist and 5-HT
1A receptor agonist, and it has been demonstrated that the latter property contributes to its overall therapeutic effects.
Vasodilation of the
blood vessel
The blood vessels are the components of the circulatory system that transport blood throughout the human body. These vessels transport blood cells, nutrients, and oxygen to the tissues of the body. They also take waste and carbon dioxide away ...
s in the
skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other animal coverings, such as the arthropod exoskeleton, have different de ...
via central 5-HT
1A activation increases
heat
In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary. A thermodynamic system does not ''contain'' heat. Nevertheless, the term is ...
dissipation
In thermodynamics, dissipation is the result of an irreversible process that takes place in homogeneous thermodynamic systems. In a dissipative process, energy ( internal, bulk flow kinetic, or system potential) transforms from an initial form to ...
from the organism out into the environment, causing a decrease in
body temperature
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature ...
.
Activation of central 5-HT
1A receptors triggers the release or inhibition of
norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad' ...
depending on species, presumably from the
locus coeruleus, which then reduces or increases neuronal tone to the
iris sphincter muscle by modulation of
postsynaptic
Chemical synapses are biological junctions through which neurons' signals can be sent to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous sys ...
α2-adrenergic receptors within the
Edinger-Westphal nucleus, resulting in
pupil dilation in
rodent
Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are n ...
s, and
pupil constriction in
primate
Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians ( monkeys and apes, the latter including ...
s including
human
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...
s.
5-HT
1A receptor agonists like
buspirone
Buspirone, sold under the brand name Buspar, among others, is a medication primarily used to treat anxiety disorders, particularly generalized anxiety disorder. Benefits support its short-term use. It is taken by mouth, and it may take up to fo ...
and
flesinoxan show efficacy in relieving
anxiety
Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...
and
depression,
and buspirone and
tandospirone
Tandospirone (brand name Sediel) is an anxiolytic and antidepressant drug used in China and Japan, where it is marketed by Dainippon Sumitomo Pharma. It is a member of the azapirone class of drugs and is closely related to other azapirones l ...
are currently approved for these indications in various parts of the world. Others such as
gepirone
Gepirone is an antidepressant and anxiolytic drug of the azapirone group that was synthesized by Bristol-Myers Squibb in 1986 and has been under development for the treatment of depression but has yet to be marketed. It has been under developmen ...
,
flesinoxan,
flibanserin
Flibanserin, sold under the brand name Addyi, is a medication approved for the treatment of pre-menopausal women with hypoactive sexual desire disorder (HSDD). The medication improves sexual desire, increases the number of satisfying sexual eve ...
, and
naluzotan have also been investigated, though none have been fully developed and approved yet. Some of the
atypical antipsychotic
The atypical antipsychotics (AAP), also known as second generation antipsychotics (SGAs) and serotonin–dopamine antagonists (SDAs), are a group of antipsychotic drugs (antipsychotic drugs in general are also known as major tranquilizers and ne ...
s like
lurasidone
Lurasidone, sold under the trade name Latuda among others, is an antipsychotic medication used to treat schizophrenia and bipolar disorder. It is taken by mouth.
Common side effects include sleepiness, movement disorders, nausea, and diarrhea. ...
and
aripiprazole
Aripiprazole, sold under the brand names Abilify and Aristada among others, is an atypical antipsychotic. It is primarily used in the treatment of schizophrenia and bipolar disorder. Other uses include as an add-on treatment in major depressiv ...
are also
partial agonist
In pharmacology, partial agonists are drugs that bind to and activate a given receptor, but have only partial efficacy at the receptor relative to a full agonist. They may also be considered ligands which display both agonistic and antagonis ...
s at the 5-HT
1A receptor and are sometimes used in low doses as augmentations to standard
antidepressants like the
selective serotonin reuptake inhibitor
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracellul ...
s (SSRIs). Mice lacking 5-HT
1A receptors altogether (
knockout) show increased anxiety but lower depressive-like behaviour.
5-HT
1A autoreceptor desensitization and increased 5-HT
1A receptor postsynaptic activation via general increases in serotonin levels by serotonin
precursor
Precursor or Precursors may refer to:
* Precursor (religion), a forerunner, predecessor
** The Precursor, John the Baptist
Science and technology
* Precursor (bird), a hypothesized genus of fossil birds that was composed of fossilized parts of u ...
supplementation,
serotonin reuptake inhibition, or
inhibition
Inhibitor or inhibition may refer to:
In biology
* Enzyme inhibitor, a substance that binds to an enzyme and decreases the enzyme's activity
* Reuptake inhibitor, a substance that increases neurotransmission by blocking the reuptake of a neurotra ...
of
monoamine oxidase has been shown to be a major mediator in the therapeutic benefits of most mainstream
antidepressant supplements and
pharmaceutical
A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field an ...
s, including serotonin precursors like
L-tryptophan
Tryptophan (symbol Trp or W)
is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an Alpha_and_beta_carbon , α-amino group, an α-carboxylic acid group, and a side chain indole, making it a polar molecule with ...
and
5-HTP, SSRIs,
serotonin-norepinephrine reuptake inhibitors (SNRIs),
tricyclic antidepressant
Tricyclic antidepressants (TCAs) are a class of medications that are used primarily as antidepressants, which is important for the management of depression. They are second-line drugs next to SSRIs. TCAs were discovered in the early 1950s and wer ...
s (TCAs),
tetracyclic antidepressant
Tetracyclic antidepressants (TeCAs) are a class of antidepressants that were first introduced in the 1970s. They are named after their tetracyclic chemical structure, containing four rings of atoms, and are closely related to the tricyclic ant ...
s (TeCAs), and
monoamine oxidase inhibitors (MAOIs).
5-HT
1A receptor activation likely plays a significant role in the positive effects of serotonin
releasing agent
A monoamine releasing agent (MRA), or simply monoamine releaser, is a drug that induces the synapse, release of a monoamine neurotransmitter from the synapse, presynaptic neuron into the synapse, leading to an increase in the extracellular conc ...
s (SRAs) like
MDMA
3,4-Methylenedioxymethamphetamine (MDMA), commonly seen in tablet form (ecstasy) and crystal form (molly or mandy), is a potent empathogen–entactogen with stimulant properties primarily used for recreational purposes. The desire ...
(commonly known as ecstasy) as well.
5-HT
1A receptors in the
dorsal raphe nucleus
The dorsal raphe nucleus is located on the midline of the brainstem and is one of the raphe nuclei. It has rostral and caudal subdivisions.
* The rostral aspect of the ''dorsal'' raphe is further divided into interfascicular, ventral, ventrolatera ...
are co-localized with
neurokinin 1
The tachykinin receptor 1 (TACR1) also known as neurokinin 1 receptor (NK1R) or substance P receptor (SPR) is a G protein coupled receptor found in the central nervous system and peripheral nervous system. The endogenous ligand for this receptor ...
(NK
1) receptors and have been shown to inhibit the release of
substance P
Substance P (SP) is an undecapeptide (a peptide composed of a chain of 11 amino acid residues) and a member of the tachykinin neuropeptide family. It is a neuropeptide, acting as a neurotransmitter and as a neuromodulator. Substance P and its clo ...
, their
endogenous ligand
In coordination chemistry, a ligand is an ion or molecule ( functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's elec ...
.
In addition to being
antidepressant and
anxiolytic
An anxiolytic (; also antipanic or antianxiety agent) is a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxiet ...
in effect, 5-HT
1A receptor activation has also been demonstrated to be
antiemetic
An antiemetic is a drug that is effective against vomiting and nausea. Antiemetics are typically used to treat motion sickness and the side effects of opioid analgesics, general anaesthetics, and chemotherapy directed against cancer. They m ...
and
analgesic,
and all of these properties may be mediated in part or full, depending on the property in question, by NK
1 receptor inhibition. Consequently, novel
NK1 receptor antagonists are now in use for the treatment of
nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...
and
emesis
Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose.
Vomiting can be the result of ailments like food poisoning, gastroenteriti ...
, and are also being investigated for the treatment of anxiety and depression.
5-HT
1A receptor activation has been shown to increase
dopamine release in the
medial prefrontal cortex
In mammalian brain anatomy, the prefrontal cortex (PFC) covers the front part of the frontal lobe of the cerebral cortex. The PFC contains the Brodmann areas BA8, BA9, BA10, BA11, BA12, BA13, BA14, BA24, BA25, BA32, BA44, BA45, BA4 ...
,
striatum, and
hippocampus
The hippocampus (via Latin from Greek , ' seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, ...
, and may be useful for improving the symptoms of
schizophrenia
Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social wit ...
and
Parkinson's disease
Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...
.
As mentioned above, some of the atypical antipsychotics are 5-HT
1A receptor partial agonists, and this property has been shown to enhance their clinical efficacy.
Enhancement of dopamine release in these areas may also play a major role in the antidepressant and anxiolytic effects seen upon postsynaptic activation of the 5-HT
1A receptor.
The activation of 5-HT
1A receptors has been demonstrated to impair certain aspects of
memory
Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembered ...
(affecting declarative and non-declarative memory functions) and
learning (due to interference with memory-encoding mechanisms), by inhibiting the release of
glutamate and
acetylcholine in various areas of the
brain
A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a ve ...
.
5-HT
1A activation is known to improve cognitive functions associated with the prefrontal cortex, possibly via inducing prefrontal cortex dopamine and acetylcholine release. Conversely, the 5-HT
1A antagonist,
WAY100635, alleviated learning and memory impairments induced by
glutamate blockade (with
dizocilpine
Dizocilpine (INN), also known as MK-801, is a pore blocker of the ''N''-Methyl-D-aspartate (NMDA) receptor, a glutamate receptor, discovered by a team at Merck in 1982. Glutamate is the brain's primary excitatory neurotransmitter. The channel is ...
) or hippocampal cholinergic denervation (by
fornix transection) in primates. Furthermore, 5-HT
1A receptor
antagonists such as
lecozotan have been shown to facilitate certain types of learning and memory in rodents, and as a result, are being developed as novel treatments for
Alzheimer's disease.
Other effects of 5-HT
1A activation that have been observed in scientific research include:
* Decreased
aggression
* Increased
sociability
Social behavior is behavior among two or more organisms within the same species, and encompasses any behavior in which one member affects the other. This is due to an interaction among those members. Social behavior can be seen as similar to an ...
* Decreased
impulsivity
* Inhibition of
drug-seeking behavior
Substance dependence, also known as drug dependence, is a biopsychological situation whereby an individual's functionality is dependent on the necessitated re-consumption of a psychoactive substance because of an adaptive state that has develope ...
* Facilitation of
sex drive
Libido (; colloquial: sex drive) is a person's overall sexual drive or desire for sexual activity. Libido is influenced by biological, psychological, and social factors. Biologically, the sex hormones and associated neurotransmitters that act up ...
and
arousal
* Inhibition of
penile erection
An erection (clinically: penile erection or penile tumescence) is a physiological phenomenon in which the penis becomes firm, engorged, and enlarged. Penile erection is the result of a complex interaction of psychological, neural, vascular, ...
*
Diminished food intake
* Prolongation of
REM sleep
Sleep is a sedentary state of mind and body. It is characterized by altered consciousness, relatively inhibited sensory activity, reduced muscle activity and reduced interactions with surroundings. It is distinguished from wakefulness by a de ...
latency
* Reversal of
opioid
Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid use ...
-induced
respiratory depression
Endocrinology
5-HT
1A receptor activation induces the
secretion of various
hormone
A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are require ...
s including
cortisol,
corticosterone
Corticosterone, also known as 17-deoxycortisol and 11β,21-dihydroxyprogesterone, is a 21-carbon steroid hormone of the corticosteroid type produced in the cortex of the adrenal glands. It is of minor importance in humans, except in the very rar ...
,
adrenocorticotropic hormone
Adrenocorticotropic hormone (ACTH; also adrenocorticotropin, corticotropin) is a polypeptide tropic hormone produced by and secreted by the anterior pituitary gland. It is also used as a medication and diagnostic agent. ACTH is an important c ...
(ACTH),
oxytocin,
prolactin
Prolactin (PRL), also known as lactotropin, is a protein best known for its role in enabling mammals to produce milk. It is influential in over 300 separate processes in various vertebrates, including humans. Prolactin is secreted from the pit ...
,
growth hormone
Growth hormone (GH) or somatotropin, also known as human growth hormone (hGH or HGH) in its human form, is a peptide hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals. It is thus important in h ...
, and
β-endorphin
''beta''-Endorphin (β-endorphin) is an endogenous opioid neuropeptide and peptide hormone that is produced in certain neurons within the central nervous system and peripheral nervous system. It is one of three endorphins that are produced ...
.
The receptor does not affect
vasopressin
Human vasopressin, also called antidiuretic hormone (ADH), arginine vasopressin (AVP) or argipressin, is a hormone synthesized from the AVP gene as a peptide prohormone in neurons in the hypothalamus, and is converted to AVP. It then trave ...
or
renin
Renin (etymology and pronunciation), also known as an angiotensinogenase, is an aspartic protease protein and enzyme secreted by the kidneys that participates in the body's renin–angiotensin–aldosterone system (RAAS)—also known as the r ...
secretion, unlike the
5-HT2 receptors.
It has been suggested that oxytocin release may contribute to the prosocial,
antiaggressive, and anxiolytic properties observed upon activation of the receptor.
β-Endorphin secretion may contribute to antidepressant, anxiolytic, and analgesic effects.
Autoreceptors
5-HT
1A receptors can be located on the
cell body,
dendrite
Dendrites (from Greek δένδρον ''déndron'', "tree"), also dendrons, are branched protoplasmic extensions of a nerve cell that propagate the electrochemical stimulation received from other neural cells to the cell body, or soma, of the ...
s,
axon
An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action p ...
s, and both
presynaptic
In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell.
Synapses are essential to the transmission of nervous impulses from ...
ally and
postsynaptic
Chemical synapses are biological junctions through which neurons' signals can be sent to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous sys ...
ally in
nerve terminal
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system.
A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the e ...
s or
synapses. Those located on the soma and dendrites are referred to as
somatodendritic, and those located presynaptically in the synapse are simply referred to as presynaptic. As a group, receptors that are sensitive to the neurotransmitter that is released by the neuron on which the receptors are located are known as
autoreceptor
An autoreceptor is a type of receptor located in the membranes of nerve cells. It serves as part of a negative feedback loop in signal transduction. It is only sensitive to the neurotransmitters or hormones released by the neuron on which the au ...
s; they typically constitute the key component of an ultra-short negative feedback loop whereby the neuron's release of neurotransmitter inhibits its further release of neurotransmitter. Stimulation of 5-HT
1A autoreceptors inhibits the release of serotonin in nerve terminals. For this reason, 5-HT
1A receptor agonists tend to exert a biphasic mode of action; they decrease serotonin release and postsynaptic 5-HT
1A receptor activity in low doses, and further decrease serotonin release but increase postsynaptic 5-HT
1A receptor activity at higher doses by directly stimulating the receptors in place of serotonin.
This autoreceptor-mediated inhibition of serotonin release has been theorized to be a major factor in the therapeutic lag that is seen with serotonergic antidepressants such as the SSRIs.
The autoreceptors must first
desensitize before the concentration of extracellular serotonin in the synapse can become elevated appreciably.
Though the responsiveness of the autoreceptors is somewhat reduced with chronic treatment, they still remain effective at constraining large increases in extracellular serotonin concentrations.
For this reason,
serotonin reuptake inhibitor
A serotonin reuptake inhibitor (SRI) is a type of drug which acts as a reuptake inhibitor of the neurotransmitter serotonin (5-hydroxytryptamine, or 5-HT) by blocking the action of the serotonin transporter (SERT). This in turn leads to incre ...
s that also have 5-HT
1A receptor antagonistic or partial agonistic properties, such as
vilazodone
Vilazodone, sold under the brand name Viibryd among others, is a medication used to treat major depressive disorder. It is taken by mouth.
Common side effects include nausea, diarrhea, and trouble sleeping. Serious side effects may include in ...
and
SB-649,915
SB-649,915 is a serotonin reuptake inhibitor and 5-HT1A and 5-HT1B receptor antagonist which is being investigated for its antidepressant effects. Relative to the selective serotonin reuptake inhibitors (SSRIs), SB-649,915 has a faster onset ...
, are being investigated and introduced as novel antidepressants with the potential for a faster onset of action and improved effectiveness compared to those currently available.
Unlike most drugs that elevate extracellular serotonin levels like the SSRIs and MAOIs, SRAs such as
fenfluramine
Fenfluramine, sold under the brand name Fintepla, is a serotonergic medication used for the treatment of seizures associated with Dravet syndrome and Lennox–Gastaut syndrome.https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/212102s003lb ...
and
MDMA
3,4-Methylenedioxymethamphetamine (MDMA), commonly seen in tablet form (ecstasy) and crystal form (molly or mandy), is a potent empathogen–entactogen with stimulant properties primarily used for recreational purposes. The desire ...
bypass serotonin autoreceptors such as 5-HT
1A. They do this by directly acting on the release mechanisms of serotonin neurons and forcing release to occur regardless of autoreceptor-mediated inhibition.
As such, SRAs induce immediate and much greater increases in extracellular serotonin concentrations compared to other serotonin-elevating agents such as the SSRIs. [Note: This is questionable as the level of serotonin output from SRAs is still dose dependant and, while SRAs will initially bypass autoreceptors, the increase in serotonin they induce will then agonise autoreceptors.] In contrast to SRAs, SSRIs may decrease serotonin levels initially (especially at lower dosages due to the biphasic mode of action mentioned above) and require several weeks of chronic dosing before serotonin concentrations reach their maximal elevation (due to 1A autoreceptor desensitization) and full clinical benefits for conditions such as depression and anxiety are seen
(although other studies show an acute increase in 5-HT
which may account for initial worsening of symptoms in sensitive individuals
). For these reasons,
selective serotonin releasing agent
A serotonin releasing agent (SRA) is a type of drug that induces the release of serotonin into the neuronal synaptic cleft. A selective serotonin releasing agent (SSRA) is an SRA with less significant or no efficacy in producing neurotransmitter ...
s (SSRAs) such as
MDAI
MDAI (5,6-methylenedioxy-2-aminoindane) is a drug developed in the 1990s by a team led by David E. Nichols at Purdue University. It acts as a non-neurotoxic and highly selective serotonin releasing agent (SSRA) ''in vitro'' and produces entact ...
and
MMAI have been proposed as novel antidepressants with a putatively faster onset of action and improved effectiveness compared to current treatments.
Similarly to SRAs, sufficiently high doses of 5-HT
1A receptor agonists also bypass the 5-HT
1A autoreceptor-mediated inhibition of serotonin release and therefore increase 5-HT
1A postsynaptic receptor activation by directly agonizing the postsynaptic receptors
in lieu of serotonin.
Ligands
The distribution of 5-HT
1A receptors in the
human brain
The human brain is the central organ of the human nervous system, and with the spinal cord makes up the central nervous system. The brain consists of the cerebrum, the brainstem and the cerebellum. It controls most of the activities of the ...
may be imaged with the
positron emission tomography using the
radioligand
A radioligand is a radioactive biochemical substance (in particular, a ligand (biochemistry), ligand that is radioactive tracer, radiolabeled) that is used for diagnosis or for research-oriented study of the receptor (biochemistry), receptor system ...
11C">sup>11CWAY-100,635
WAY-100635 is a piperazine drug and research chemical widely used in scientific studies. It was originally believed to act as a selective 5-HT1A receptor antagonist, but subsequent research showed that it also acts as potent full agonist at ...
.
For example, one study has found increased 5-HT
1A binding in type 2
diabetes
Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ...
.
Another PET study found a negative correlation between the amount of 5-HT
1A binding in the
raphe nuclei,
hippocampus
The hippocampus (via Latin from Greek , ' seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, ...
and
neocortex and a self-reported tendency to have
spiritual experience
A religious experience (sometimes known as a spiritual experience, sacred experience, or mystical experience) is a subjective experience which is interpreted within a religious framework. The concept originated in the 19th century, as a defense ...
s.
Labeled with
tritium
Tritium ( or , ) or hydrogen-3 (symbol T or H) is a rare and radioactive isotope of hydrogen with half-life about 12 years. The nucleus of tritium (t, sometimes called a ''triton'') contains one proton and two neutrons, whereas the nucleus of ...
, WAY-100,635 may also be used in
autoradiography.
Agonists
Partial agonists
*
2C-B
*
2C-E
*
2C-T-2
*
4C-T-2
*
5-CT
*
5-MT
*
5-MeO-DiPT
*
5-MeO-DMT
*
5-MeO-MiPT
*
5-MeO-TMT
*
6-F-DMT
*
Adatanserin
*
αET
*
Amphetamine
*
αMT
*
Aripiprazole
Aripiprazole, sold under the brand names Abilify and Aristada among others, is an atypical antipsychotic. It is primarily used in the treatment of schizophrenia and bipolar disorder. Other uses include as an add-on treatment in major depressiv ...
*
Asenapine
Asenapine, sold under the brand name Saphris among others, is an atypical antipsychotic medication used to treat schizophrenia and acute mania associated with bipolar disorder.
It was chemically derived via altering the chemical structure of the ...
*
Bacoside
*
Bay R 1531
Bay R 1531 is a tricyclic tryptamine derivative which acts as a selective serotonin receptor 5-HT1A agonist. It was researched unsuccessfully for the treatment of stroke but remains in use for scientific research.
See also
* 8-OH-DPAT
* RDS- ...
*
Befiradol
Befiradol (F-13,640; NLX-112) is an experimental drug being studied for the treatment of levodopa-induced dyskinesia. It is a potent and selective 5-HT1A receptor full agonist.
Pharmacology
In recombinant cell lines expressing human 5-HT1A ...
*
Binospirone
Binospirone (MDL-73,005-EF) is a drug which acts as a partial agonist at 5-HT1A somatodendritic autoreceptors but as an antagonist at postsynaptic 5-HT1A receptors. It has anxiolytic effects.
See also
* Azapirone
Azapirones are a class of ...
*
Brexpiprazole
Brexpiprazole, sold under the brand name Rexulti among others, is an atypical antipsychotic. It is a dopamine D2 receptor partial agonist and has been described as a "serotonin–dopamine activity modulator" (SDAM). The drug was approved by th ...
*
Bufotenin
Bufotenin (5-HO-DMT, bufotenine) is a tryptamine derivative - more specifically, a DMT derivative - related to the neurotransmitter serotonin. It is an alkaloid found in some species of toads (especially the skin), mushrooms and plants.
...
*
Buspirone
Buspirone, sold under the brand name Buspar, among others, is a medication primarily used to treat anxiety disorders, particularly generalized anxiety disorder. Benefits support its short-term use. It is taken by mouth, and it may take up to fo ...
(postsynaptic 5-HT
1A)
*
Cannabidiol
Cannabidiol (CBD) is a phytocannabinoid discovered in 1940. It is one of 113 identified cannabinoids in cannabis plants, along with tetrahydrocannabinol (THC), and accounts for up to 40% of the plant's extract. , clinical research on CBD in ...
*
Cariprazine
Cariprazine, sold under the brand names Vraylar and Reagila among others, is an on oral atypical antipsychotic originated by Gedeon Richter, which is used in the treatment of schizophrenia, bipolar mania, and bipolar depression. It acts prim ...
*
Clozapine
Clozapine is a psychiatric medication and is the first atypical antipsychotic (also called second-generation antipsychotic). It is primarily used to treat people with schizophrenia and schizoaffective disorders who have had an inadequate respo ...
*
''cis''-LSZ
*
Dihydroergotamine
*
Dimethyltryptamine
''N'',''N''-Dimethyltryptamine (DMT or ''N'',''N''-DMT, SPL026) is a substituted tryptamine that occurs in many plants and animals, including human beings, and which is both a derivative and a structural analog of tryptamine. It is used as a ...
*
DiPT
Diisopropyltryptamine (; also known as ''N,N''-diisopropyltryptamine or DiPT) is a psychedelic hallucinogenic drug of the tryptamine family that has a unique effect. While the majority of hallucinogens affect the visual sense, DiPT is primarily ...
*
DOET
2,5-Dimethoxy-4-ethylamphetamine (DOET, DOE, Hecate) is a psychedelic drug of the phenethylamine and amphetamine chemical classes. It was first synthesized by Alexander Shulgin, and was described in his book '' PiHKAL'' (''Phenethylamines i Hav ...
*
DOI
*
DPT DPT may refer to:
Science and medicine
* Dpt (unit) (dioptre/diopter), most commonly a unit measuring refraction and power in a lens or curved mirror
*Dermatopontin, a human extracellular matrix protein
* Dipropyltryptamine, a psychedelic tryptami ...
*
Ebalzotan
Ebalzotan (NAE-086) is a selective 5-HT1A receptor agonist. It was under development as an antidepressant and anxiolytic agent but produced undesirable side effects in phase I clinical trials and was subsequently discontinued.
See also
* 4 ...
*
Eltoprazine
Eltoprazine (developmental code name DU-28,853) is a serotonergic drug of the phenylpiperazine class which is described as a serenic or antiaggressive agent. It acts as an agonist of the serotonin 5-HT1A, 5-HT1A and 5-HT1B, 5-HT1B receptors and a ...
*
EMDT
2-Ethyl-5-methoxy-''N'',''N''-dimethyltryptamine (EMDT) is a tryptamine derivative which is used in scientific research. It acts as a selective 5-HT6 receptor agonist, with a Ki of 16 nM, and was one of the first selective agonists developed ...
*
Ergotamine
Ergotamine, sold under the brand names Cafergot (with caffeine) and Ergomar among others, is an ergopeptine and part of the ergot family of alkaloids; it is structurally and biochemically closely related to ergoline. It possesses structural sim ...
*
Etoperidone
Etoperidone, associated with several brand names, is an atypical antidepressant which was developed in the 1970s and either is no longer marketed or was never marketed. It is a phenylpiperazine related to trazodone and nefazodone in chemical str ...
*
F-11,461
*
F-12,826
F1 is Formula One, the highest class of auto racing sanctioned by the FIA.
F1, F01, F.I, F.1 or F-1 may refer to:
Computing
* F1, a computer Function key
* F1, an Office Assistant in Microsoft Office
* F1 Magazine, a Syrian monthly computer ...
*
F-13,714
*
F-14,679
*
Flesinoxan
*
Flibanserin
Flibanserin, sold under the brand name Addyi, is a medication approved for the treatment of pre-menopausal women with hypoactive sexual desire disorder (HSDD). The medication improves sexual desire, increases the number of satisfying sexual eve ...
*
Ginkgo biloba
''Ginkgo biloba'', commonly known as ginkgo or gingko ( ), also known as the maidenhair tree, is a species of tree native to China. It is the last living species in the order Ginkgoales, which first appeared over 290 million years ago. Fossil ...
*
Gepirone
Gepirone is an antidepressant and anxiolytic drug of the azapirone group that was synthesized by Bristol-Myers Squibb in 1986 and has been under development for the treatment of depression but has yet to be marketed. It has been under developmen ...
*
Haloperidol
Haloperidol, sold under the brand name Haldol among others, is a typical antipsychotic medication. Haloperidol is used in the treatment of schizophrenia, tics in Tourette syndrome, mania in bipolar disorder, delirium, agitation, acute psychosi ...
*
Lamotrigine
*
Ipsapirone
Ipsapirone is a selective 5-HT1A receptor partial agonist of the piperazine and azapirone chemical classes. It has antidepressant and anxiolytic effects. Ipsapirone was studied in several placebo-controlled trials for depression and continues ...
*
Limonene
Limonene is a colorless liquid aliphatic hydrocarbon classified as a cyclic monoterpene, and is the major component in the oil of citrus fruit peels. The -isomer, occurring more commonly in nature as the fragrance of oranges, is a flavoring a ...
*
Lisuride
Lisuride, sold under the brand name Dopergin among others, is a monoaminergic medication of the ergoline class which is used in the treatment of Parkinson's disease, migraine, and high prolactin levels. It is taken by mouth.
Side effects of lis ...
*
Lurasidone
Lurasidone, sold under the trade name Latuda among others, is an antipsychotic medication used to treat schizophrenia and bipolar disorder. It is taken by mouth.
Common side effects include sleepiness, movement disorders, nausea, and diarrhea. ...
*
LY-301,317
*
Lysergic acid diethylamide
Lysergic acid diethylamide (LSD), also known colloquially as acid, is a potent psychedelic drug. Effects typically include intensified thoughts, emotions, and sensory perception. At sufficiently high dosages LSD manifests primarily mental, vi ...
(LSD)
*
Mescaline
*
3,4-Methylenedioxyamphetamine (MDA)
*
3,4-Methylenedioxymethamphetamine (MDMA)
*
Methylphenidate
Methylphenidate, sold under the brand names Ritalin and Concerta among others, is the most widely prescribed central nervous system (CNS) stimulant medication used to treat attention deficit hyperactivity disorder (ADHD) and, to a lesser exten ...
*
Methysergide
Methysergide, sold under the brand names Deseril and Sansert, is a monoaminergic medication of the ergoline and lysergamide groups which is used in the prophylaxis and treatment of migraine and cluster headaches. It has been withdrawn from the ma ...
*
Naluzotan
*
NBUMP
*
Nefazodone
Nefazodone, sold formerly under the brand names Serzone, Dutonin, and Nefadar among others, is an atypical antidepressant which was first marketed by Bristol-Myers Squibb (BMS) in 1994 but has since largely been discontinued. BMS withdrew it from ...
*
Olanzapine
Olanzapine (sold under the trade name Zyprexa among others) is an atypical antipsychotic primarily used to treat schizophrenia and bipolar disorder. For schizophrenia, it can be used for both new-onset disease and long-term maintenance. It is t ...
*
Osemozotan (postsynaptic 5-HT
1A)
*
Perospirone
Perospirone (Lullan) is an atypical antipsychotic of the azapirone family. It was introduced in Japan by Dainippon Sumitomo Pharma in 2001 for the treatment of schizophrenia and acute cases of bipolar mania.
Medical uses
Its primary uses are i ...
*
Pyrimidinylpiperazine
*
Piclozotan
Piclozotan (SUN-N4057) is a selective 5-HT1A receptor partial agonist, which has neuroprotective effects in animal studies. It has been through early clinical trials in humans for treatment of acute stroke, but results have not yet been announ ...
*
Psilocin
Psilocin (also known as 4-HO-DMT, 4-hydroxy DMT, psilocine, psilocyn, or psilotsin) is a substituted tryptamine alkaloid and a serotonergic psychedelic substance. It is present in most psychedelic mushrooms together with its phosphorylated cou ...
*
Psilocybin
Psilocybin ( , ) is a naturally occurring psychedelic prodrug compound produced by more than 200 species of fungi. The most potent are members of the genus ''Psilocybe'', such as '' P. azurescens'', '' P. semilanceata'', and '' P.&nbs ...
*
Quetiapine
Quetiapine, sold under the brand name Seroquel among others, is an atypical antipsychotic medication used for the treatment of schizophrenia, bipolar disorder, and major depressive disorder. Despite being widely used as a sleep aid due to its ...
*
Rauwolscine
Rauwolscine, also known as isoyohimbine, α-yohimbine, and corynanthidine, is an alkaloid found in various species within the genera ''Rauvolfia'' and ''Corynanthe'' (including ''Pausinystalia''). It is a stereoisomer of yohimbine. Rauwolscine is ...
*
Roxindole
Roxindole (EMD-49,980) is a dopaminergic and serotonergic drug which was originally developed by Merck KGaA for the treatment of schizophrenia. In clinical trials its antipsychotic efficacy was only modest but it was unexpectedly found to produc ...
*
RR-2B
*
RU-24,969
*
S-15,535
*
Sarizotan
*
SS-2C
*
SSR-181,507
*
Sunepitron
*
Tandospirone
Tandospirone (brand name Sediel) is an anxiolytic and antidepressant drug used in China and Japan, where it is marketed by Dainippon Sumitomo Pharma. It is a member of the azapirone class of drugs and is closely related to other azapirones l ...
*
Tiospirone
*
Trazodone
Trazodone, sold under many brand names, is an antidepressant medication. It is used to treat major depressive disorder, anxiety disorders, and difficulties with sleep. The medication is taken orally.
Common side-effects include dry mouth, f ...
*
Trifluoromethylphenylpiperazine
3-Trifluoromethylphenylpiperazine (TFMPP) is a recreational drug of the piperazine chemical class. Usually in combination with benzylpiperazine (BZP) and other analogues, it is sold as an alternative to the illicit drug MDMA ("Ecstasy").
Pharm ...
*
Trimethoxyamphetamine
Trimethoxyamphetamines (TMAs) are a family of isomeric psychedelic hallucinogenic drugs. There exist six different TMAs that differ only in the position of the three methoxy groups: TMA, TMA-2, TMA-3, TMA-4, TMA-5, and TMA-6. The TMAs are anal ...
*
Umespirone
Umespirone (KC-9172) is a drug of the azapirone class which possesses anxiolytic and antipsychotic properties. It behaves as a 5-HT1A receptor partial agonist (Ki = 15 nM), D2 receptor partial agonist (Ki = 23 nM), and α1-adrenoceptor recepto ...
*
Urapidil
Urapidil is a sympatholytic antihypertensive drug. It acts as an α1-adrenoceptor antagonist and as an 5-HT1A receptor agonist. Although an initial report suggested that urapidil was also an α2-adrenoceptor agonist, this was not substantiated ...
*
Vilazodone
Vilazodone, sold under the brand name Viibryd among others, is a medication used to treat major depressive disorder. It is taken by mouth.
Common side effects include nausea, diarrhea, and trouble sleeping. Serious side effects may include in ...
*
Xaliproden
Xaliproden (codenamed SR57746) is a drug which acts as a 5HT1A agonist. It has neurotrophic and neuroprotective effects ''in vitro'', and has been proposed for use in the treatment of several neurodegenerative conditions including amyotrophic ...
*
Yohimbine
Yohimbine (), also known as quebrachine, is an indole alkaloid derived from the bark of the African tree '' Pausinystalia johimbe''; also from the bark of the unrelated South American tree ''Aspidosperma quebracho-blanco''. Yohimbine is an α2 ...
*
Zalospirone
*
Ziprasidone
Ziprasidone, sold under the brand name Geodon among others, is an atypical antipsychotic used to treat schizophrenia and bipolar disorder. It may be used by mouth and by injection into a muscle (IM). The IM form may be used for acute agitation ...
Full agonists
*
8-OH-DPAT
8-OH-DPAT is a research chemical of the aminotetralin chemical class which was developed in the 1980s and has been widely used to study the function of the 5-HT1A receptor. It was one of the first major 5-HT1A receptor full agonists to be discove ...
*
Alnespirone
Alnespirone (S-20,499) is a selective 5-HT1A receptor full agonist of the azapirone chemical class. It has antidepressant and anxiolytic effects.
See also
* 8-OH-DPAT
* Azapirone
Azapirones are a class of drugs used as anxiolytics, anti ...
*
Buspirone
Buspirone, sold under the brand name Buspar, among others, is a medication primarily used to treat anxiety disorders, particularly generalized anxiety disorder. Benefits support its short-term use. It is taken by mouth, and it may take up to fo ...
(presynaptic 5HT1A)
*
Befiradol
Befiradol (F-13,640; NLX-112) is an experimental drug being studied for the treatment of levodopa-induced dyskinesia. It is a potent and selective 5-HT1A receptor full agonist.
Pharmacology
In recombinant cell lines expressing human 5-HT1A ...
*
Tetrahydrocannabivarin (THCV)
*
Eptapirone
Eptapirone (F-11,440) is a very potent and highly selective 5-HT1A receptor full agonist of the azapirone family. Its affinity for the 5-HT1A receptor was reported to be 4.8 nM (Ki) (or 8.33 (pKi)), and its intrinsic activity approximately e ...
*
F-15,599
F-15,599, also known as NLX-101, is a potent and selective 5-HT1A receptor full agonist. It displays functional selectivity (also known as "biased agonism") by strongly activating 5-HT1A receptors in the postsynaptic prefrontal cortex while h ...
*
Lesopitron
*
MKC-242
*
LY-293,284
LY-293284 is a research chemical developed by the pharmaceutical company Eli Lilly and used for scientific studies. It acts as a potent and selective 5-HT1A receptor full agonist. It was derived through structural simplification of the ergoline ...
*
Osemozotan (presynaptic 5-HT
1A)
*
Repinotan
Repinotan (BAYx3702), an aminomethylchroman derivative, is a selective 5-HT1A receptor full agonist with high potency and efficacy. It has neuroprotective effects in animal studies, and was trialed in humans for reducing brain injury following h ...
*
U-92,016-A
*
Flibanserin
Flibanserin, sold under the brand name Addyi, is a medication approved for the treatment of pre-menopausal women with hypoactive sexual desire disorder (HSDD). The medication improves sexual desire, increases the number of satisfying sexual eve ...
*
Vortioxetine
Vortioxetine, sold under the brand names Trintellix and Brintellix among others, is a medication used to treat major depressive disorder. Effectiveness is viewed as similar to that of other antidepressants. It is taken by mouth.
Common side e ...
Biased agonists
* HBK-17 –
β-arrestin biased agonist
* NLX-204 –
ERK1
Mitogen-activated protein kinase 3, also known as p44MAPK and ERK1, is an enzyme that in humans is encoded by the ''MAPK3'' gene.
Function
The protein encoded by this gene is a member of the mitogen-activated protein kinase (MAP kinase) fami ...
/
2 preferring agonist
Antagonists
*
Alprenolol
*
AV-965
*
Binospirone
Binospirone (MDL-73,005-EF) is a drug which acts as a partial agonist at 5-HT1A somatodendritic autoreceptors but as an antagonist at postsynaptic 5-HT1A receptors. It has anxiolytic effects.
See also
* Azapirone
Azapirones are a class of ...
(postsynaptic 5-HT
1A)
*
BMY-7,378
*
Cannabigerol
Cannabigerol (CBG) is one of more than 120 identified cannabinoid compounds found in the plant genus ''Cannabis''. Cannabigerol is the decarboxylated form of cannabigerolic acid, the parent molecule from which other cannabinoids are synthesized ...
*
Cyanopindolol
*
Cyproheptadine
Cyproheptadine, sold under the brand name Periactin among others, is a first-generation antihistamine, first-generation antihistamine with additional anticholinergic, antiserotonergic, and local anesthetic properties.
It was patented in 1959 an ...
*
Dotarizine
*
Flopropione
Flopropione (Compacsul, Cospanon, Ecapron, Pellegal, Argobyl, Floveton, Saritron, Spamorin, Labrodax, Tryalon, Mirulevatin, Padeskin, Profenon) is a spasmolytic or antispasmodic agent. It acts as a COMT inhibitor
Inhibitor or inhibition may ...
*
GR-46,611
*
Iodocyanopindolol
*
Isamoltane
*
Lecozotan
*
Mefway
Mefway is a serotonin 5-HT1A receptor antagonist used in medical research, usually in the form of mefway ( 18F) as a positron emission tomography (PET) radiotracer.
Chemistry
Mefway is closely related to the research compound WAY-100,635. ...
*
Methiothepin
Metitepine (; developmental code names Ro 8-6837 (maleate), VUFB-6276 (mesylate)), also known as methiothepin, is a drug described as a " psychotropic agent" of the tricyclic group which was never marketed. It acts as a non-selective antagonis ...
*
MPPF
*
NAN-190
*
Nebivolol
Nebivolol is a beta blocker used to treat high blood pressure and heart failure. As with other β-blockers, it is generally a less preferred treatment for high blood pressure. It may be used by itself or with other blood pressure medication. It ...
*
Oxprenolol
Oxprenolol (brand names Trasacor, Trasicor, Coretal, Laracor, Slow-Pren, Captol, Corbeton, Slow-Trasicor, Tevacor, Trasitensin, Trasidex) is a non-selective beta blocker with some intrinsic sympathomimetic activity. It is used for the treatment o ...
*
Pindobind
*
Pindolol
Pindolol, sold under the brand name Visken among others, is a nonselective beta blocker which is used in the treatment of hypertension.Drugs.coInternational brand names for pindolol Page accessed Sept 4, 2015 It is also an antagonist of the se ...
(presynaptic 5-HT
1A)
*
Propranolol
Propranolol, sold under the brand name Inderal among others, is a medication of the beta blocker class. It is used to treat high blood pressure, a number of types of irregular heart rate, thyrotoxicosis, capillary hemangiomas, performance an ...
*
Risperidone
Risperidone, sold under the brand name Risperdal among others, is an atypical antipsychotic used to treat schizophrenia and bipolar disorder. It is taken either by mouth or by injection (subcutaneous or intramuscular). The injectable versions ...
(weak)
*
Robalzotan
Robalzotan (NAD-299, AZD-7371) is a selective antagonist at the 5-HT1A receptor. It was shown to completely reverse the autoreceptor-mediated inhibition of serotonin release induced by the administration of selective serotonin reuptake inhibito ...
*
SB-649,915
SB-649,915 is a serotonin reuptake inhibitor and 5-HT1A and 5-HT1B receptor antagonist which is being investigated for its antidepressant effects. Relative to the selective serotonin reuptake inhibitors (SSRIs), SB-649,915 has a faster onset ...
*
SDZ-216,525
*
Spiperone
Spiperone (Spiroperidol; brand name: Spiropitan ( JP)) is a typical antipsychotic and research chemical belonging to the butyrophenone chemical class. It is licensed for clinical use in Japan as a treatment for schizophrenia. Additionally, spip ...
*
Spiramide
*
Spiroxatrine
Spiroxatrine is a drug which acts as a selective antagonist at both the 5-HT1A receptor and the α2C adrenergic receptor. It is an analog of spiperone
Spiperone (Spiroperidol; brand name: Spiropitan ( JP)) is a typical antipsychotic and re ...
*
UH-301
(S)-UH-301 is a drug and research chemical widely used in scientific studies. It acts as a selective 5-HT1A receptor silent antagonist. It is structurally related to 8-OH-DPAT. UH-301 was found to produce a head-twitch response in mice which is ...
*
WAY-100,135
*
WAY-100,635
WAY-100635 is a piperazine drug and research chemical widely used in scientific studies. It was originally believed to act as a selective 5-HT1A receptor antagonist, but subsequent research showed that it also acts as potent full agonist at ...
*
Xylamidine
Xylamidine is a drug which acts as an Antagonist (pharmacology), antagonist at the 5-HT2A receptor, 5HT2A Receptor (biochemistry), receptor, and to a lesser extent at the 5HT1A receptor. It does not cross the blood–brain barrier, which makes it ...
Allosteric Modulators
*
Cholesterol
Cholesterol is any of a class of certain organic molecules called lipids. It is a sterol (or modified steroid), a type of lipid. Cholesterol is biosynthesized by all animal cells and is an essential structural component of animal cell mem ...
– endogenous
PAM
*
Oleamide
Oleamide is an organic compound with the formula CH3(CH2)7CH=CH(CH2)7CONH2(. It is the amide derived from the fatty acid oleic acid. It is a colorless waxy solid and occurs in nature. Sometimes labeled as a fatty acid primary amide (FAPA), it is ...
– endogenous PAM
* Zn2+ – endogenous NAM
*
AM-2201
AM-2201 (1-(5-fluoropentyl)-3-(1-naphthoyl)indole) is a recreational designer drug that acts as a potent but nonselective full agonist for the cannabinoid receptor. It is part of the AM series of cannabinoids discovered by Alexandros Makriyanni ...
– exogenous PAM
Genetics
The 5-HT
1A receptor is coded by the ''HTR1A''
gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
. There are several human
polymorphisms associated with this gene. A 2007 review listed 27
single nucleotide polymorphisms (SNP).
The most investigated SNPs are C-1019G (
rs6295
rs6295, also called C(-1019)G, is a gene variation—a single nucleotide polymorphism (SNP)—in the HTR1A gene. It is one of the most investigated SNPs of its gene.
The C-allele is the most prevalent with 0.675 against the G-allele with 0.325 amo ...
), C-1018G,
Ile28Val (
rs1799921), Arg219Leu (
rs1800044), and Gly22Ser (
rs1799920).
Some of the other SNPs are Pro16Leu, Gly272Asp, and the
synonymous polymorphism G294A (
rs6294). These gene variants have been studied in relation to
psychiatric disorder
A mental disorder, also referred to as a mental illness or psychiatric disorder, is a behavioral or mental pattern that causes significant distress or impairment of personal functioning. Such features may be persistent, relapsing and remitt ...
s with no definitive results.
Protein-protein interactions
The 5-HT
1A receptor has been shown to
interact
Advocates for Informed Choice, dba interACT or interACT Advocates for Intersex Youth, is a 501(c)(3) nonprofit organization using innovative strategies to advocate for the legal and human rights of children with intersex traits. The organizati ...
with
brain-derived neurotrophic factor
Brain-derived neurotrophic factor (BDNF), or abrineurin, is a protein found in the and the periphery. that, in humans, is encoded by the ''BDNF'' gene. BDNF is a member of the neurotrophin family of growth factors, which are related to the canon ...
(BDNF), which may play a major role in its regulation of mood and anxiety.
Receptor oligomers
The 5-HT
1A receptor forms
heterodimers with the following receptors:
5-HT7,
5-HT1B,
5-HT1D,
GABAB2,
LPA1 (GPCR26),
LPA3,
S1P1,
S1P3.
See also
*
5-HT receptor
*
5-HT1 receptor
References
External links
*
*
{{DEFAULTSORT:5-Ht1a Receptor
Serotonin receptors