ABSTRACT
The beneficial effects of organic nitrates in ischemic heart diseases have been known since 1867, but it is only recently that it became fully recognized that they act by releasing nitric oxide in the vascular wall, perhaps substituting for a lack in endogenous nitrate. It is possible that nitric oxide radical [NO] in high concentrations can, at least theoretically, have adverse influences on the antioxidant profile of human blood cells [Erythrocytes and Leukocytes]. The effects of various doses of isosorbide dinitrate [ISDN] in inducing a stste of oxidative stress in blood cells which may be reflected in changes in the following parameters: [Cytosolic glutathione, lipid peroxidation, and antioxidant enzymes activities] were examined, and it is found that, a dose dependent increase in lipid peroxidation and a depletion of cytosolic glutathione was occurred, with subsequent alterathions in the activities of the antioxidant enzymes [glutathione-S- transferase [GST], glutathione reductase [GSR], glutathione peroxidase [GSH-Px], Superoxide dismutase [SOD] and Catalase [CAT]]. These results reflect worsening effects of the state of oxidative stress previously induced by ischemic changes in the myocardium.