The serotonin 1A receptor (or 5-HT_1A receptor) is a subtype of

serotonin receptor 5-HT receptors, 5-hydroxytryptamine receptors, or serotonin receptors, are a group of G protein-coupled receptor and ligand-gated ion channels found in the central and peripheral nervous systems. They mediate both excitatory and inhibitory ne ...

, or 5-HT receptor, that binds

serotonin Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and va ...

, also known as 5-HT, a

neurotransmitter A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell. Neu ...

. 5-HT1A is expressed in the

brain A brain is an organ (biology), 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 Visual perception, vision. I ...

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% consisting o ...

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 syste ...

septum In biology, a septum (Latin for ''something that encloses''; plural septa) is a wall, dividing a cavity or structure into smaller ones. A cavity or structure divided in this way may be referred to as septate. Examples Human anatomy * Interat ...

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 ver ...

, 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 ext ...

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 direct ...

. The 5-HT_1A receptors in the raphe nucleus are largely

somatodendritic 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 syste ...

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 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 n ...

agonist An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ag ...

s 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 Blood pressure (BP) is the pressure of circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term "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 A sympatholytic (or sympathoplegic) drug is a medication that opposes the downstream effects of postganglionic nerve firing in effector organs innervated by the sympathetic nervous system (SNS). They are indicated for various functions; for example ...

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 th ...

drug A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via inhala ...

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 substantiate ...

is an α₁-adrenergic receptor

antagonist An antagonist is a character in a story who is presented as the chief foe of the protagonist. Etymology The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, ri ...

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 awa ...

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 ...

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 temperatur ...

. 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 The locus coeruleus () (LC), also spelled locus caeruleus or locus ceruleus, is a nucleus in the pons of the brainstem involved with physiological responses to stress and panic. It is a part of the reticular activating system. The locus coer ...

, which then reduces or increases neuronal tone to the

iris sphincter muscle The iris sphincter muscle (pupillary sphincter, pupillary constrictor, circular muscle of iris, circular fibers) is a muscle in the part of the eye called the iris. It encircles the pupil of the iris, appropriate to its function as a constricto ...

by modulation of postsynaptic α₂-adrenergic receptors within the Edinger-Westphal nucleus, resulting in

pupil dilation Pupillary response is a physiological response that varies the size of the pupil, via the optic and oculomotor cranial nerve. A constriction response (miosis), is the narrowing of the pupil, which may be caused by scleral buckles or drugs such ...

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 includin ...

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, cultu ...

s. 5-HT_1A receptor agonists like buspirone and

flesinoxan Flesinoxan (DU-29,373) is a potent and selective 5-HT1A receptor partial/near- full agonist of the phenylpiperazine class. Originally developed as a potential antihypertensive drug, flesinoxan was later found to possess antidepressant and anx ...

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 li ...

are currently approved for these indications in various parts of the world. Others such as gepirone,

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 even ...

, 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 and aripiprazole 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

antidepressant Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common Side effect, side-effects of antidepressants include Xerostomia, dry mouth, weig ...

s 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 A knockout (abbreviated to KO or K.O.) is a fight-ending, winning criterion in several full-contact combat sports, such as boxing, kickboxing, muay thai, mixed martial arts, karate, some forms of taekwondo and other sports involving strikin ...

) 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 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 increase ...

, or inhibition of

monoamine oxidase Monoamine oxidases (MAO) () are a family of enzymes that catalyze the oxidation of monoamines, employing oxygen to clip off their amine group. They are found bound to the outer membrane of mitochondria in most cell types of the body. The firs ...

has been shown to be a major mediator in the therapeutic benefits of most mainstream

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 and ...

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 α-amino group, an α-carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromatic ...

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 inhibitor Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, esp ...

s (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 are co-localized with neurokinin 1 (NK₁) 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 Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell. In contrast, exogenous substances and processes are those that originate from outside of an organism. For example, ...

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 elect ...

. In addition to being

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 An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of drugs used to achieve relief from pain (that is, analgesia or pain management). It ...

, and all of these properties may be mediated in part or full, depending on the property in question, by NK₁ 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 th ...

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 Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. Dopamine constitutes about 80% o ...

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 The striatum, or corpus striatum (also called the striate nucleus), is a nucleus (a cluster of neurons) in the subcortical basal ganglia of the forebrain. The striatum is a critical component of the motor and reward systems; receives gluta ...

, and

, 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 w ...

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 beco ...

. 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 remember ...

(affecting declarative and non-declarative memory functions) and

learning Learning is the process of acquiring new understanding, knowledge, behaviors, skills, values, attitudes, and preferences. The ability to learn is possessed by humans, animals, and some machines; there is also evidence for some kind of lea ...

(due to interference with memory-encoding mechanisms), by inhibiting the release of

glutamate Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can synt ...

and

acetylcholine Acetylcholine (ACh) is an organic chemical that functions in the brain and body of many types of animals (including humans) as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Par ...

in various areas of the

. 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

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

s 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 Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As ...

. Other effects of 5-HT_1A activation that have been observed in scientific research include: * Decreased

aggression Aggression is overt or covert, often harmful, social interaction with the intention of inflicting damage or other harm upon another individual; although it can be channeled into creative and practical outlets for some. It may occur either reacti ...

* 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 In psychology, impulsivity (or impulsiveness) is a tendency to act on a whim, displaying behavior characterized by little or no forethought, reflection, or consideration of the consequences. Impulsive actions are typically "poorly conceived, prema ...

* Inhibition of drug-seeking behavior * Facilitation of sex drive and

arousal Arousal is the physiological and psychological state of being awoken or of sense organs stimulated to a point of perception. It involves activation of the ascending reticular activating system (ARAS) in the brain, which mediates wakefulness, th ...

* Inhibition of penile erection * Diminished food intake * Prolongation of

REM Rem or REM may refer to: Music * R.E.M., an American rock band * ''R.E.M.'' (EP), by Green * "R.E.M." (song), by Ariana Grande Organizations * La République En Marche!, a French centrist political party * Reichserziehungsministerium, in Nazi ...

sleep Sleep is a sedentary state of mind and body. It is characterized by altered consciousness, relatively inhibited Perception, sensory activity, reduced muscle activity and reduced interactions with surroundings. It is distinguished from wakefuln ...

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 Hypoventilation (also known as respiratory depression) occurs when ventilation is inadequate (''hypo'' meaning "below") to perform needed respiratory gas exchange. By definition it causes an increased concentration of carbon dioxide (hypercapni ...

Endocrinology

5-HT_1A receptor activation induces the

secretion 440px Secretion is the movement of material from one point to another, such as a secreted chemical substance from a cell or gland. In contrast, excretion is the removal of certain substances or waste products from a cell or organism. The classic ...

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 required ...

s including

cortisol Cortisol is a steroid hormone, in the glucocorticoid class of hormones. When used as a medication, it is known as hydrocortisone. It is produced in many animals, mainly by the '' zona fasciculata'' of the adrenal cortex in the adrenal g ...

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 Oxytocin (Oxt or OT) is a peptide hormone and neuropeptide normally produced in the hypothalamus and released by the posterior pituitary. It plays a role in social bonding, reproduction, childbirth, and the period after childbirth. Oxytoc ...

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 pi ...

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 ...

, 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 produc ...

. 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 ...

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 ...

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 The soma (pl. ''somata'' or ''somas''), perikaryon (pl. ''perikarya''), neurocyton, or cell body is the bulbous, non-process portion of a neuron or other brain cell type, containing the cell nucleus. The word 'soma' comes from the Greek '' σῶμ ...

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 ...

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 presynaptically and postsynaptically 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 ...

s or

synapse 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 ...

s. Those located on the soma and dendrites are referred to as

, 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

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 inhibitors 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 Oral administration, by mouth. Common side effects include nausea, diarrhea, and trouble sleeping. Serious side ef ...

and SB-649,915, 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/2022/212102s003l ...

and

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 e ...

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 entacto ...

and

MMAI 5-Methoxy-6-methyl-2-aminoindane (MMAI) 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) and produces entactogen effects in ...

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 Many words in the English vocabulary are of French origin, most coming from the Anglo-Norman spoken by the upper classes in England for several hundred years after the Norman Conquest, before the language settled into what became Modern Engl ...

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 ...

may be imaged with the

positron emission tomography Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, ...

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 ...

sup>11C

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 the ...

. 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,

and

neocortex The neocortex, also called the neopallium, isocortex, or the six-layered cortex, is a set of layers of the mammalian cerebral cortex involved in higher-order brain functions such as sensory perception, cognition, generation of motor commands, sp ...

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 An autoradiograph is an image on an X-ray film or nuclear emulsion produced by the pattern of decay emissions (e.g., beta particles or gamma rays) from a distribution of a radioactive substance. Alternatively, the autoradiograph is also available ...

Agonists

Partial agonists

2C-B 2C-B (4-Bromo-2,5-dimethoxyphenethylamine) is a psychedelic drug of the 2C family. It was first synthesized by Alexander Shulgin in 1974. In Shulgin's book '' PiHKAL'', the dosage range is listed as 12–24 mg. As a recreational drug, 2C-B is so ...

2C-E 2C-E is a psychedelic phenethylamine of the 2C family. It was first synthesized by Alexander Shulgin and documented in his book '' PiHKAL''. Like the other substances in its family, it produces sensory and cognitive effects in its physical reactio ...

2C-T-2 2C-T-2 is a psychedelic and entactogenic phenethylamine of the 2C family. It was first synthesized in 1981 by Alexander Shulgin, and rated by him as one of the "magical half-dozen" most important psychedelic phenethylamine compounds. The drug h ...

4C-T-2 2,5-Dimethoxy-4-ethylthio-α-ethylphenethylamine (4C-T-2) is a synthetic drug of the phenethylamine chemical class. It is the α- ethylated analogue of 2C-T-2. Pharmacology Binding profile 4C-T-2 has affinity (Ki) for the 5-HT1A (5,339 ...

* 5-CT * 5-MT *

5-MeO-DiPT 5-Methoxy-''N'',''N''-diisopropyltryptamine (5-MeO-DiPT, sometimes called Foxy Methoxy or simply Foxy) is a psychedelic tryptamine and the methoxy derivative of diisopropyltryptamine (DiPT). Pharmacology The mechanism that produces the purport ...

5-MeO-DMT 5-MeO-DMT (5-methoxy-''N'',''N''-dimethyltryptamine) or O-methyl-bufotenin is a psychedelic of the tryptamine class. It is found in a wide variety of plant species, and also is secreted by the glands of at least one toad species, the Colorado R ...

* 5-MeO-MiPT * 5-MeO-TMT * 6-F-DMT * Adatanserin * αET *

Amphetamine Amphetamine (contracted from alpha- methylphenethylamine) is a strong central nervous system (CNS) stimulant that is used in the treatment of attention deficit hyperactivity disorder (ADHD), narcolepsy, and obesity. It is also commonly used ...

* αMT * Aripiprazole * Asenapine * Bacoside * Bay R 1531 * Befiradol * Binospirone *

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 the ...

* Bufotenin * Buspirone (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 * Clozapine * ''cis''-LSZ *

Dihydroergotamine Dihydroergotamine (DHE), sold under the brand names D.H.E. 45 and Migranal among others, is an ergot alkaloid used to treat migraines. It is a derivative of ergotamine. It is administered as a nasal spray or injection and has an efficacy simi ...

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 * DOET * 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 * Eltoprazine * EMDT *

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 st ...

* F-11,461 * F-12,826 * F-13,714 * F-14,679 *

Flesinoxan Flesinoxan (DU-29,373) is a potent and selective 5-HT1A receptor partial/near- full agonist of the phenylpiperazine class. Originally developed as a potential antihypertensive drug, flesinoxan was later found to possess antidepressant and anx ...

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 even ...

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. Fossils ...

* Gepirone * Haloperidol *

Lamotrigine Lamotrigine, sold under the brand name Lamictal among others, is a medication used to treat epilepsy and stabilize mood in bipolar disorder. For epilepsy, this includes focal seizures, tonic-clonic seizures, and seizures in Lennox-Gastaut sy ...

* Ipsapirone *

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 * 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 Mescaline or mescalin (3,4,5-trimethoxyphenethylamine) is a naturally occurring psychedelic protoalkaloid of the substituted phenethylamine class, known for its hallucinogenic effects comparable to those of LSD and psilocybin. Biological ...

* 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 extent ...

* Methysergide * 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 * Psilocin *

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 * Roxindole * 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 li ...

Tiospirone Tiospirone (BMY-13,859), also sometimes called tiaspirone or tiosperone, is an atypical antipsychotic of the azapirone class. It was investigated as a treatment for schizophrenia in the late 1980s and was found to have an effectiveness equivalent ...

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"). Pharma ...

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 analogs ...

* Umespirone *

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 substantiate ...

Vilazodone Vilazodone, sold under the brand name Viibryd among others, is a medication used to treat major depressive disorder. It is taken Oral administration, by mouth. Common side effects include nausea, diarrhea, and trouble sleeping. Serious side ef ...

* Xaliproden *

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 Zalospirone (WY-47,846) is a selective 5-HT1A partial agonist of the azapirone chemical class. It was found to be effective in the treatment of anxiety and depression in clinical trial Clinical trials are prospective biomedical or behavi ...

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 agitati ...

Full agonists

* 8-OH-DPAT * Alnespirone * Buspirone (presynaptic 5HT1A) * Befiradol * Tetrahydrocannabivarin (THCV) * Eptapirone * F-15,599 * Lesopitron * MKC-242 * LY-293,284 * 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 *

* Vortioxetine

Biased agonists

* HBK-17 –

β-arrestin Arrestins (abbreviated Arr) are a small family of proteins important for regulating signal transduction at G protein-coupled receptors. Arrestins were first discovered as a part of a conserved two-step mechanism for regulating the activity ...

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) famil ...

/ 2 preferring agonist

Antagonists

* Alprenolol * AV-965 * Binospirone (postsynaptic 5-HT_1A) *

BMY-7,378 BMY-7,378 is a 5-HT1A receptor weak 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 considere ...

* Cannabigerol * 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 * 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. Th ...

* Methiothepin *

MPPF MPPF, with the full name 2'-methoxyphenyl-(''N''-2'-pyridinyl)-''p''-fluoro-benzamidoethyipiperazine, is a compound that binds to the serotonin-1A receptor. Labeled with fluorine-18 it has been used as a radioligand with positron emission tomogr ...

NAN-190 NAN-190 is a drug and research chemical widely used in scientific studies. It was previously believed to act as a selective 5-HT1A receptor antagonist, but a subsequent discovery showed that it also potently blocks the α2-adrenergic receptor. ...

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. I ...

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 ...

* 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 inhibit ...

* SB-649,915 * 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 Spiramide (developmental code name AMI-193) is an experimental antipsychotic that acts as a selective 5-HT2A, 5-HT1A, and D2 receptor antagonist. It has negligible affinity Affinity may refer to: Commerce, finance and law * Affinity (l ...

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 and also has some dopamine antagonist A dopamine antagonist, also known as an anti-dopam ...

* UH-301 * WAY-100,135 *

Xylamidine Xylamidine is a drug which acts as an antagonist at the 5HT2A receptor, and to a lesser extent at the 5HT1A receptor. It does not cross the blood–brain barrier, which makes it useful for blocking peripheral serotonergic responses like cardio ...

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 memb ...

– 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 ...

– endogenous PAM * Zn2+ – endogenous NAM * AM-2201 – exogenous PAM

Genetics

The 5-HT_1A receptor is coded by the ''HTR1A''

. There are several human polymorphisms associated with this gene. A 2007 review listed 27

single nucleotide polymorphism In genetics, a single-nucleotide polymorphism (SNP ; plural SNPs ) is a germline substitution of a single nucleotide at a specific position in the genome. Although certain definitions require the substitution to be present in a sufficiently larg ...

s (SNP). The most investigated SNPs are C-1019G ( rs6295), C-1018G, Ile28Val ( rs1799921), Arg219Leu (

rs1800044 The RS-18 is a reconfigured version of the Rocketdyne Lunar Module Ascent Engine (LMAE), modified to burn liquid oxygen (LOX) and liquid methane (CH4) for NASA's Exploration Systems Architecture Study (ESAS) engine testing in 2008. Development ...

), 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, doing business as, 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 trai ...

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 In biochemistry, a protein dimer is a macromolecular complex formed by two protein monomers, or single proteins, which are usually non-covalently bound. Many macromolecules, such as proteins or nucleic acids, form dimers. The word ''dimer'' has ...

with the following receptors: 5-HT₇, 5-HT_1B, 5-HT_1D, GABA_B2, LPA₁ (GPCR26), LPA₃, S1P₁, S1P₃.

References

External links

* * {{DEFAULTSORT:5-Ht1a Receptor Serotonin receptors