The Sound of Evolution
Melatonin
Mechanism of action:
Melatonin is an endogenous neurohormone primarily secreted by the pineal gland. Melatonin mainly acts on MT1 and MT2 receptors in the central nervous system, both of which are highly expressed in the suprachiasmatic nucleus of the hypothalamus, the central regulator of the body's circadian clock. MT1 suppresses neuronal firing and promotes sleep initiation and maintenance, whereas MT2 regulates and resets circadian phase shifting.
Reference(s):
1. Boutin JA et al. (2005). Molecular tools to study melatonin pathways and actions. Trends Pharmacol Sci.
2. Caniato R et al. (2003). Melatonin in plants. Adv Exp Med Biol.
3. Hardeland R et al. (2005). Antioxidative protection by melatonin: multiplicity of mechanisms from radical detoxification to radical avoidance. Endocrine.