5-hydroxytryptamine receptor 1B also known as the 5-HT_1B receptor is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

that in humans is encoded by the ''HTR1B''

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 ...

. The 5-HT_1B receptor is a

5-HT 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 ...

subtype.

Tissue distribution and function

5-HT_1B receptors are widely distributed throughout 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 ...

with the highest concentrations found in the frontal cortex,

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 ...

, striatum, and the

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, ...

. The function of the 5-HT_1B receptor differs depending upon its location. In the frontal cortex, it is believed to act as a postsynaptic receptor inhibiting the release of dopamine. In the basal ganglia and the striatum, evidence suggests 5-HT signaling acts on an

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 ...

, inhibiting the release of serotonin and decreasing glutamatergic transmission by reducing miniature

excitatory postsynaptic potential In neuroscience, an excitatory postsynaptic potential (EPSP) is a postsynaptic potential that makes the postsynaptic neuron more likely to fire an action potential. This temporary depolarization of postsynaptic membrane potential, caused by the ...

(mEPSP) frequency, respectively. In the hippocampus, a recent study has demonstrated that activation of postsynaptic 5-HT_1B

heteroreceptor A heteroreceptor is a receptor regulating the synthesis and/or the release of mediators other than its own ligand. Heteroreceptors respond to neurotransmitters, neuromodulators, or neurohormones released from adjacent neurons or cells; they are o ...

s produces a facilitation in excitatory synaptic transmission which is altered in depression. When the expression of 5-HT_1B in human cortex was traced throughout life, significant changes during adolescence were observed, in a way that is strongly correlated with the expression of 5-HT_1E. Outside of the CNS, the 5-HT_1B receptor is also expressed on the

endothelium The endothelium is a single layer of squamous endothelial cells that line the interior surface of blood vessels and lymphatic vessels. The endothelium forms an interface between circulating blood or lymph in the lumen and the rest of the vesse ...

of blood vessels, particularly in the meninges. Activation of these receptors results in

vasoconstriction Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vess ...

. The high distribution of vasoconstrictive 5-HT_1B and 5-HT_1D receptors around the brain makes them a valuable drug target for the treatment of migraines. Blocking 5-HT_1B receptor signalling also increases the number of osteoblasts, bone mass, and the bone formation rate. * Knockout mice lacking the 5-HT_1B gene have been reported to have a higher preference for alcohol, although later studies failed to replicate such abnormalities in alcohol consumption. These mice have also been reported to have a lower measure of anxiety (such as on the elevated plus maze test) and a higher measure of aggression. Under basal conditions, knockout mice present with a "normal" phenotype and exhibit a sucrose preference (lack of sucrose preference is considered a measure of anhedonia). However, after undergoing chronic unpredictable stress treatment to induce a "depression-like" phenotype these animals do not benefit from administration of

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 ...

(SSRIs).

Ligands

Agonists

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 ...

(vasoconstrictor in migraine) *

Oxymetazoline Oxymetazoline, sold under the brand name Afrin among others, is a topical decongestant and vasoconstrictor medication. It is available over-the-counter as a nasal spray to treat nasal congestion and nosebleeds, as eyedrops to treat eye rednes ...

* Sumatriptan (vasoconstrictor in migraine) * Zolmitriptan * 5-Carboxamidotryptamine * CGS-12066A * CP-93,129 (peripherally acting) * CP-94,253 *

CP-122,288 CP-122,288 is a drug which acts as a potent and selective agonist for the 5-HT1B, 5-HT1D and 5-HT1F serotonin receptor subtypes. It is a derivative of the migraine medication sumatriptan, but while CP-122,288 is 40,000 times more potent th ...

(mixed 5-HT_1B/1D agonist) * CP-135,807 (mixed 5-HT_1B/1D agonist) * RU-24969 (mixed 5-HT_1A/1B agonist)

Partial agonists

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 ...

(

antipsychotic Antipsychotics, also known as neuroleptics, are a class of psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range of ...

) *

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 ...

(

) *

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 ...

( antidepressant)

Antagonists and inverse agonists

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 ...

(

) *

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 ...

(

aphrodisiac An aphrodisiac is a substance that increases sexual desire, sexual attraction, sexual pleasure, or sexual behavior. Substances range from a variety of plants, spices, foods, and synthetic chemicals. Natural aphrodisiacs like cannabis or cocai ...

) *

Metergoline Metergoline (, ), also known as methergoline and sold under the brand names Contralac (veterinary) and Liserdol (clinical), is a monoaminergic medication of the ergoline group which is used as a prolactin inhibitor in the treatment of hyperprola ...

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 ...

* Isamoltane * AR-A000002 *

SB-216,641 SB-216641 is a drug which is a selective antagonist for the serotonin receptor 5-HT1B, with around 25x selectivity over the closely related 5-HT1D receptor. It is used in scientific research, and has demonstrated anxiolytic An anxiolyti ...

* SB-224,289 (inverse agonist) * SB-236,057 (inverse agonist)

Undetermined Action

Dextromethorphan Dextromethorphan (DXM) is a medication most often used as a cough suppressant in over-the-counter cold and cough medicines. It is sold in syrup, tablet, spray, and lozenge forms. In 2022, the FDA approved a formulation of it combined with bu ...

( Cough Suppressant)

Genetics

In humans the protein is coded by the gene ''HTR1B''. A genetic variant in the promoter region, '' A-161T'', has been examined with respect to

personality trait In psychology, trait theory (also called dispositional theory) is an approach to the study of human personality. Trait theorists are primarily interested in the measurement of ''traits'', which can be defined as habitual patterns of behaviour, tho ...

s and showed no major effect.

References

External links

* * * {{DEFAULTSORT:5-Ht1b Receptor Serotonin receptors Biology of attention deficit hyperactivity disorder