H2O2-INDUCED LIPID-PEROXIDATION IN RAT-BRAIN HOMOGENATES IS GREATLY REDUCED BY MELATONIN

Melatonin protection against H2O2-induced lipid peroxidation in brain homogenates was measured in vitro. The level of malonaldehyde (MDA) pl us 4-hydroxyalkenals (4-HDA) was assayed in brain homogenates as an in dex of induced membrane oxidative damage. Brain homogenates were co-in cubated with H2O2 alone or in combination with melatonin. Brain MDA 4-HDA increased after H2O2 (0.1-5 mM) with the effect being both conce ntration- and time-dependent. Melatonin (0.1-5 mM) protected against H 2O2-induced lipid peroxidation of brain homogenates in a concentration -dependent manner.