Melatonin Receptor (None)

Melatonin receptors are a class of G-protein coupled receptors (GPCRs) that mediate the physiological effects of melatonin, a hormone primarily involved in regulating circadian rhythms and sleep-wake cycles. The two main subtypes in humans are MT1 and MT2. MT1 is primarily involved in sleep initiation and maintenance, vasoconstriction, and inhibition of prolactin secretion. MT2 mediates phase-shifting effects on circadian rhythms, promotes vasodilation, regulates retinal physiology and osteoblast function, and is associated with anxiolytic effects. Both subtypes act via Gi/o proteins, leading to inhibition of adenylate cyclase activity and reduced cAMP levels. They are targets for drugs treating insomnia, sleep disorders, and neuropsychiatric conditions.

Agonism or antagonism of MT1 and/or MT2 receptors, leading to modulation of downstream signaling pathways primarily involving inhibition of adenylate cyclase and reduced cAMP levels.