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Melatonin receptors in the central nervous system.

The functional role of melatonin receptors in the mammalian central nervous system and their therapeutic potential is discussed. Melatonin, dubbed the “hormone of darkness,” is produced primarily in the pineal gland and retina following circadian rhythms with high levels of night. The chapter describes the structure, molecular pharmacology, signaling, and function of the MT1 and MT2 mammalian melatonin receptors. This is followed by discussion of recent advances in the regulation of melatonin receptor sensitivity and its role in circadian rhythm modulation by the circadian timing system. Recent advances in the discovery and development of therapeutic agents targeting melatonin receptors for the treatment of insomnia, circadian rhythm dysfunctions, and depression are also highlighted. 
 
 
Keywords: 
 
MT1 and MT2 melatonin receptors; 
luzindole; 
4P-PDOT; 
suprachiasmatic nucleus; 
circadian rhythms; 
sleep; 
depression