Melatonin (N-acetyl-5-methoxytryptamine) is synthesized from an essential amino acid tryptophan. It is a pineal gland neurohormone. Direct, non-receptor-mediated free radical scavenging activity induced by melatonin, makes it unique from other classic hormones. Melatonin is expressed in variety of organisms such as bacteria, algae, fungi, plants, insects, and vertebrates including humans.
Melatonin has been administered to experimental animals for following studies:
- To determine if long-term melatonin administration is able to induce reproductive changes and how melatonin exerts its protective action related to lipid oxidation and antioxidant activities in the rat ovary during ovulation.
- To determine the effect of melatonin on endoplasmic reticulum stress and sirtuin 1 expression in neuronal cells of newborn rats after hypoxia–ischemia.
- To study the effect of melatonin on chronic stress-induced gut dysfunction in stressed mice.