5-hydroxytryptamine receptor 1A and 5-hydroxytryptamine receptor 1B (5-HT1A/1B)

The 5-HT1A and 5-HT1B receptors are subtypes of the serotonin (5-hydroxytryptamine) receptor family, belonging to the G protein-coupled receptor (GPCR) superfamily [1, 2]. Both receptors are primarily coupled to Gi/o proteins, leading to the inhibition of adenylyl cyclase and a subsequent decrease in intracellular cAMP levels [1, 12]. 5-HT1A receptors are widely distributed in the brain, acting as both presynaptic autoreceptors in the raphe nuclei and postsynaptic heteroreceptors in limbic regions, where they modulate mood, anxiety, and cognitive functions [1, 4, 5]. 5-HT1B receptors are found on presynaptic terminals and in vascular smooth muscle, where they regulate neurotransmitter release and mediate vasoconstriction, particularly in cranial blood vessels [2, 12, 13]. These receptors are key therapeutic targets; 5-HT1A agonists and partial agonists like buspirone and vilazodone are used to treat generalized anxiety disorder and major depressive disorder [1, 5, 7]. 5-HT1B agonists, such as the triptan class (e.g., sumatriptan), are the mainstay for acute migraine treatment due to their vasoconstrictive effects [12, 13]. Dysregulation of these receptors is implicated in various neuropsychiatric conditions, including schizophrenia, Parkinson's disease, and addiction [1, 4, 8, 13].

Other names

Serotonin 1A and 1B receptorsHTR1A/HTR1B5-HT1A/1B5-hydroxytryptamine 1A/1B receptors

Agonism, partial agonism, and antagonism of the 5-HT1A and 5-HT1B receptors to modulate serotonergic signaling and vascular tone [1, 3, 12].