Melatonin Receptor 1 (MT1) Antibodies

The melatonin receptor MT₁ is a class A G protein-coupled receptor that mediates many of the circadian and sleep-promoting effects of the hormone melatonin. Pharmacologically, it is activated by endogenous melatonin and by clinically used agonists such as ramelteon, agomelatine, and tasimelteon, which are prescribed for insomnia and circadian rhythm sleep disorders. Upon ligand binding, MT₁ primarily couples to Gi/o proteins, resulting in inhibition of adenylate cyclase, decreased intracellular cyclic AMP levels, and modulation of downstream signaling pathways that regulate neuronal firing and clock gene expression. Additional signaling mechanisms may involve phospholipase C activation, ion channel regulation, and MAP kinase pathways that contribute to neuroprotective and mood-related effects. MT₁ is highly expressed in the suprachiasmatic nucleus of the hypothalamus, the central circadian pacemaker, where it helps synchronize physiological rhythms to the light–dark cycle. Expression is also observed in the retina, pituitary gland, and several peripheral tissues, supporting broader roles in endocrine and metabolic regulation. Through these combined pharmacological, signaling, and expression characteristics, MT₁ represents an important therapeutic target for sleep and circadian rhythm disorders. For more information on MT1 receptor pharmacology please refer to the IUPHAR database. For further reading refer to: