Retinal lipid peroxidation in vitro is inhibited by melatonin

Retinal homogenates from albino rats were incubated at 37°C, with or without the pineal hormone melatonin, FeSO₄, or melatonin plus FeSO₄. Melatonin significantly diminished the increase in malonaldehyde + 4-hydroxyalkenals levels, an index of lipid peroxidation, both in the presence as well as in the absence of FeSO₄. Melatonin protection against lipid peroxidation is probably due to the newly discovered antioxidant activity of this indolamine.