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 residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

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

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

. 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 multiple tissues including the Central nervous system, central and peripheral nervous systems ...

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, spinal cord and retina. The CNS is so named because the brain integrates the received information and coordinates and influences the activity o ...

with the highest concentrations found in the

frontal cortex The frontal lobe is the largest of the four major lobes of the brain in mammals, and is located at the front of each cerebral hemisphere (in front of the parietal lobe and the temporal lobe). It is parted from the parietal lobe by a groove betw ...

basal ganglia The basal ganglia (BG) or basal nuclei are a group of subcortical Nucleus (neuroanatomy), nuclei found in the brains of vertebrates. In humans and other primates, differences exist, primarily in the division of the globus pallidus into externa ...

striatum The striatum (: striata) or corpus striatum is a cluster of interconnected nuclei that make up the largest structure of the subcortical basal ganglia. The striatum is a critical component of the motor and reward systems; receives glutamat ...

, and the

hippocampus The hippocampus (: hippocampi; via Latin from Ancient Greek, Greek , 'seahorse'), also hippocampus proper, is a major component of the brain of humans and many other vertebrates. In the human brain the hippocampus, the dentate gyrus, and the ...

. The function of the 5-HT_1B receptor differs depending upon its location. In the frontal cortex, it is believed to act as a terminal receptor inhibiting the release of

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. It is an amine synthesized ...

. In the basal ganglia and the striatum, evidence suggests 5-HT signaling acts on an

autoreceptor An autoreceptor is a type of Receptor (biochemistry), receptor located in the cell membrane, membranes of neuron, nerve cells. It serves as part of a negative feedback loop in signal transduction. It is only sensitive to the neurotransmitters or ...

, inhibiting the release of

serotonin Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, ...

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 (biochemistry), receptor located in the cell membrane of a neuron, regulating the synthesis and/or the release of mediators other than its own Ligand (biochemistry), ligand. Heteroreceptors play a crucial role in modu ...

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 (: endothelia) 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 r ...

of blood vessels, particularly in the

meninges In anatomy, the meninges (; meninx ; ) are the three membranes that envelop the brain and spinal cord. In mammals, the meninges are the dura mater, the arachnoid mater, and the pia mater. Cerebrospinal fluid is located in the subarachnoid spac ...

. 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 vesse ...

. 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

osteoblast Osteoblasts (from the Greek combining forms for " bone", ὀστέο-, ''osteo-'' and βλαστάνω, ''blastanō'' "germinate") are cells with a single nucleus that synthesize bone. However, in the process of bone formation, osteoblasts fu ...

s, bone mass, and the bone formation rate. *

Knockout mice A knockout mouse, or knock-out mouse, is a genetically modified mouse (''Mus musculus'') in which researchers have inactivated, or " knocked out", an existing gene by replacing it or disrupting it with an artificial piece of DNA. They are importan ...

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 primarily work by blo ...

(SSRIs). Activation of the serotonin 5-HT_1B receptor appears to mediate the

prosocial Prosocial behavior is a social behavior that "benefit other people or society as a whole", "such as helping, sharing, donating, co-operating, and volunteering". The person may or may not intend to benefit others; the behavior's prosocial benefi ...

effects of

entactogen Entactogens, also known as empathogens or connectogens, are a class of psychoactive drugs that induce the production of experiences of emotional communion, oneness, connectedness, emotional openness—that is, empathy—as particularly observe ...

s acting as serotonin releasing agents like

MDMA 3,4-Methylenedioxymethamphetamine (MDMA), commonly known as ecstasy (tablet form), and molly (crystal form), is an empathogen–entactogenic drug with stimulant and minor Psychedelic drug, psychedelic properties. In studies, it has been used ...

in animals. In addition, serotonin 5-HT_1B receptor activation appears to mediate the locomotor hyperactivity of these agents. The serotonin 5-HT_1B receptor also appears to be required for the persisting

antidepressant Antidepressants are a class of medications used to treat major depressive disorder, anxiety disorders, chronic pain, and addiction. Common side effects of antidepressants include Xerostomia, dry mouth, weight gain, dizziness, headaches, akathi ...

- and

anxiolytic An anxiolytic (; also antipanic or anti-anxiety 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 anxie ...

-like effects as well as acute hypolocomotion of the

serotonergic psychedelic Psychedelics are a subclass of hallucinogenic drugs whose primary effect is to trigger non-ordinary mental states (known as psychedelic experiences or "trips") and a perceived "expansion of consciousness". Also referred to as classic halluci ...

and non-selective

serotonin receptor agonist A serotonin receptor agonist is an agonist of one or more serotonin receptors. They activate serotonin receptors in a manner similar to that of serotonin (5-hydroxytryptamine; 5-HT), a neurotransmitter and hormone and the endogenous ligand of t ...

psilocybin Psilocybin, also known as 4-phosphoryloxy-''N'',''N''-dimethyltryptamine (4-PO-DMT), is a natural product, naturally occurring tryptamine alkaloid and Investigational New Drug, investigational drug found in more than List of psilocybin mushroom ...

in animals.

Ligands

Agonists

* 2ZEDMA (also a 5-HT_2A agonist) * 5-Carboxamidotryptamine (5-CT) * Almotriptan * Anpirtoline (D-16949) * Avitriptan * Batoprazine * CGS-12066A * CP-93,129 (peripherally acting) * CP-94,253 * CP-122,288 (mixed 5-HT_1B/1D agonist) * CP-135,807 (mixed 5-HT_1B/1D agonist) * Dihydroergotamine *

Donitriptan Donitriptan (International Nonproprietary Name, INN; code name F-11356) is a triptan drug which was investigated as an antimigraine agent but ultimately was never marketed. It acts as a high-affinity (pharmacology), affinity, high-efficacy (pharm ...

* Eletriptan * Eltoprazine (DU-28853) * Emodin-8-glucoside *

Ergotamine Ergotamine, sold under the brand name Ergomar among others, is an ergopeptine and part of the ergot family of alkaloids; it is structurally and biochemically closely related to ergoline. It is structurally similar to several neurotransmitter ...

* Fluprazine * Frovatriptan * L-741,604 * Lisuride * mCPP *

Methylergometrine Methylergometrine, also known as methylergonovine and sold under the brand name Methergine, is a medication of the ergoline and lysergamide groups which is used as an oxytocic in obstetrics and as an antimigraine agent in the treatment of mi ...

(methylergonovine) * Methysergide * Naratriptan * Oxymetazoline * Pergolide * PZKKN-94 (also a 5-HT₆ antagonist) * Rizatriptan * RU-24969 (mixed 5-HT_1A/1B agonist) * (S)-DCPT *

Serotonin Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, ...

Sumatriptan Sumatriptan, sold under the brand name Imitrex among others, is a medication used to treat migraine headaches and cluster headaches. It is taken Oral administration, orally, Nasal administration, intranasally, or by Subcutaneous injection, su ...

* TFMPP *

Tryptamine Tryptamine is an indolamine metabolite of the essential amino acid tryptophan. The chemical structure is defined by an indole—a fused benzene and pyrrole ring, and a 2-aminoethyl group at the second carbon (third aromatic atom, with the firs ...

psychedelics (e.g.,

5-MeO-DMT 5-MeO-DMT (5-methoxy-''N'',''N''-dimethyltryptamine), also known as ''O''-methylbufotenin or mebufotenin (), is a naturally occurring psychedelic of the tryptamine family. It is found in a wide variety of plant species, and is also secreted by ...

, DPT,

psilocin Psilocin, also known as 4-hydroxy-''N'',''N''-dimethyltryptamine (4-HO-DMT), is a substituted tryptamine alkaloid and a serotonergic psychedelic. It is present in most psychedelic mushrooms together with its phosphorylated counterpart psilocy ...

) * Zolmitriptan

Partial agonists

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 as well as the medium to long-term management of bipolar disorder. I ...

* AZ10419369 * Bromocriptine * Metergoline * Naphthylpiperazine * Vortioxetine * Ziprasidone

Antagonists and inverse agonists

* Alprenolol * AOP-208 (LB-208) * AR-A000002 (AZD-8129) *

Aripiprazole Aripiprazole, sold under the brand name Abilify, among others, is an atypical antipsychotic primarily used in the treatment of schizophrenia, bipolar disorder, and irritability associated with autism spectrum disorder; other uses include as ...

* AZD-1134 * AZD-3783 * AZ12320927 * Carteolol * Elzasonan * GR-55562 * GR-127935 * Isamoltane (CGP-361A) * LY-393558 * Metitepine (methiothepin) * NAS-181 (MCOMM) * Oxprenolol * Penbutolol *

Propranolol Propranolol is a medication of the beta blocker class. It is used to treat hypertension, high blood pressure, some types of cardiac dysrhythmia, irregular heart rate, thyrotoxicosis, capillary hemangiomas, akathisia, performance anxiety, and ...

Risperidone Risperidone, sold under the brand name Risperdal among others, is an atypical antipsychotic used to treat schizophrenia and bipolar disorder, as well as aggressive and self-injurious behaviors associated with autism spectrum disorder. It is t ...

* SB-216,641 * SB-224,289 (inverse agonist) * SB-236,057 (inverse agonist) * SB-245,570 * SB-649,915 * Tertatolol *

Yohimbine Yohimbine, also known as quebrachine, is an indole alkaloid derived from the bark of the African tree '' Pausinystalia johimbe'' (yohimbe); also from the bark of the unrelated South American tree '' Aspidosperma quebracho-blanco''. Yohimbine is ...

Unknown

Dextromethorphan Dextromethorphan, sold under the brand name Robitussin among others, is a cough suppressant used in many cough and Common cold, cold medicines. In 2022, the US Food and Drug Administration (FDA) approved the combination dextromethorphan/bupropi ...

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 behavior, thou ...

s and showed no major effect.

References

External links

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