The antioxidant and photophysical properties of melatonin: A radical perspective.

Abstract

Melatonin, or N-acetyl-5-methoxytryptamine, is an interesting neurohormone that governs the body's circadian rhythm, and is synthesized predominantly in the retina and the pineal gland, a small pea-sized gland in the centre of the brain. Since melatonin is found in low concentrations in almost all tissue, many have speculated that its biological function may include detoxification protection, but little is actually known. In the United States and other countries, such speculation has lead to a growing interest and popularity in melatonin as an over-the-counter nutritional supplement, but the lack of research and clinical trials has led to a federal ban on the sale of this neurohormone in Canada. In this thesis, our research was to investigate some molecular properties of melatonin to further the knowledge of this popular and controversial indoleamine. Examination of the photophysical and photochemical properties of melatonin have shed some light on its role in the retina, while oxygen uptake experiments have exposed some of the misconceptions regarding its antioxidant activity. (Abstract shortened by UMI.)