Serotonin receptor 1B subtype (5-HT1B receptor)

The **Serotonin receptor 1B subtype** (**5‑HT₁B receptor**) is a member of the G protein-coupled receptor family characterized by seven transmembrane domains. It is primarily located on presynaptic axons within the central nervous system—including regions such as the frontal cortex, basal ganglia, striatum—and also found on vascular endothelium. Functionally it acts as an inhibitory autoreceptor regulating serotonin release from serotonergic neurons but can also serve as a heteroreceptor modulating other neurotransmitters like dopamine and glutamate. The physiological roles include regulation of mood states, aggression levels, memory processes, stress response sensitivity and anxiety. Peripherally—especially in cerebral arteries—the activation leads to potent vasoconstriction which underlies its therapeutic targeting for migraines but also raises safety concerns regarding cardiovascular risk. Genetic variations or altered expression have been linked with neuropsychiatric conditions including addiction and obsessive-compulsive disorder.

Other names

5-hydroxytryptamine receptor 1BHTR1BSerotonin 1B receptor5-HT₁B receptor

Agonists activate the receptor to inhibit neurotransmitter release or cause vasoconstriction. Antagonists/inverse agonists block or reduce the inhibitory effect on neurotransmitter release. Drugs like triptans act as selective agonists at vascular smooth muscle to induce cranial vasoconstriction for migraine relief.