Differences in lipid peroxidation of rat liver rough and smooth microsomes

The rough and smooth microsomes of rat liver show significant differences in lipid peroxidation induced by both NADPH and ascorbate. The parameters studied include kinetics, response towards cofactors and sensitivity to inhibitors. Smooth microsomes are more prone to lipid peroxidation with increasing concentrations of NADPH, Fe3+, ascorbate and Fe2+, and are more susceptible to inhibitors than rough microsomes. Smooth microsomes also contain higher amounts of ascorbic acid, NADPH cytochrome c reductase and total lipids, besides possessing a higher degree of unsaturation in lipids, all of which promote lipid peroxidation. Our results suggest that, although smooth microsomes are more sensitive to lipid peroxidation, they are compensated for by being more sensitive to inhibitors of lipid peroxidation.