Rhythmic Control and Physiological Functional Significance of Melatonin Production in Circadian Rhythm

摘要: Circadian rhythm is controlled by hormonal oscillations governing the physiology of all living organisms. In mammals, main function pineal gland to transform circadian generated in hypothalamic suprachiasmatic nucleus into rhythmic signals circulating melatonin characterized a largely nocturnal increase that closely reflects duration night time. The has lost direct photosensitivity, but responds light via multi-synaptic pathways include subset retinal ganglion cells. Rhythmic control achieved through tight coupling between environmental lighting and arylalkylamine-N-acetyltransferase (AANAT) expression, which rhythmcontrolling enzyme synthesis. Previous studies on expression AANAT protein have described transcriptional, post-transcriptional, post-translational regulatory mechanisms. Molecular mechanisms for dependent provide novel aspects melatonin’s rhythmicity. Extensive animal research linked seasonal rhythmicity many mammalian species modulation rhythms sleep regulation. It value treating various disorders, such as jet lag or shift-work disorders. Melatonin, also, broad range effects with significant regulation influences body’s physiological functions. addition, this hormone known influence reproductive, cardiovascular, immunological well psychiatric