5-HT1B receptor

5-hydroxytryptamine receptor 1B also known as the 5-HT1B receptor is a is_associated_with::protein that in humans is encoded by the HTR1B is_associated_with::gene. The 5-HT1B receptor is a is_associated_with::5-HT receptor subtype.

Tissue distribution and function
5-HT1B receptors are widely distributed throughout the CNS with the highest concentrations found in the is_associated_with::frontal cortex, is_associated_with::basal ganglia, is_associated_with::striatum, and the is_associated_with::hippocampus. The function of the 5-HT1B receptor differs depending upon its location. In the frontal cortex, it is believed to act as a postsynaptic receptor inhibiting the release of is_associated_with::dopamine. In the basal ganglia and the striatum, evidence suggests 5-HT signaling acts on an is_associated_with::autoreceptor, inhibiting the release of is_associated_with::serotonin and decreasing glutamatergic transmission by reducing miniature is_associated_with::excitatory postsynaptic potential (mEPSP) frequency, respectively. In the hippocampus, a recent study has demonstrated that activation of postsynaptic 5-HT1B is_associated_with::heteroreceptors produces a facilitation in excitatory synaptic transmission which is altered in depression. When the expression of 5-HT1B 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-HT1E.

Outside the brain, 5-HT1B receptor activation also has vascular effects, such as pulmonary is_associated_with::vasoconstriction. Furthermore, blocking 5-HT1B receptor signaling decreases the number of is_associated_with::osteoblasts, bone mass, and the bone formation rate.

is_associated_with::Knockout mice lacking the 5-HT1B gene have shown an increase in aggression and a higher preference for alcohol. Under basal conditions, knockout mice present with a "normal" phenotype and an 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 is_associated_with::selective serotonin reuptake inhibitor (SSRIs).

Agonists

 * is_associated_with::ergotamine (vasoconstrictor in migraine)
 * is_associated_with::Oxymetazoline
 * is_associated_with::sumatriptan (vasoconstrictor in migraine)
 * is_associated_with::zolmitriptan
 * is_associated_with::5-Carboxamidotryptamine
 * is_associated_with::CGS-12066A
 * CP-93,129 (peripherally acting)
 * is_associated_with::CP-94,253
 * is_associated_with::CP-122,288 (mixed 5-HT1B/1D agonist)
 * CP-135,807 (mixed 5-HT1B/1D agonist)
 * RU-24969 (mixed 5-HT1A/1B agonist)

Partial agonists

 * is_associated_with::Vortioxetine (is_associated_with::antidepressant)
 * is_associated_with::Ziprasidone (is_associated_with::antipsychotic)
 * is_associated_with::Asenapine (is_associated_with::antipsychotic)

Antagonists and inverse agonists

 * is_associated_with::methiothepin (is_associated_with::antipsychotic)
 * is_associated_with::yohimbine (is_associated_with::aphrodisiac)
 * is_associated_with::metergoline
 * is_associated_with::Aripiprazole
 * is_associated_with::isamoltane
 * is_associated_with::AR-A000002
 * is_associated_with::SB-216,641
 * SB-224,289 (inverse agonist)
 * is_associated_with::SB-236,057 (inverse agonist)

Genetics
In humans the protein is coded by the gene HTR1B.

A genetic variant in the promotor region, is_associated_with::A-161T, has been examined with respect to is_associated_with::personality traits and showed no major effect.