CAPTOPRIL HAS NO SIGNIFICANT SCAVENGING ANTIOXIDANT ACTIVITY IN HUMANPLASMA IN-VITRO OR IN-VIVO

1 Captopril has been reported to possess hydroxyl radical(OH)and hypoc hlorous acid (HOCl) scavenging effects, which could contribute to its therapeutic activity in the clinical setting. 2 The objective of the p resent study was to determine whether therapeutically achievable capto pril concentrations could augment antioxidant properties of human plas ma and protect it against OH .- and HOCl-driven oxidant injury in vitr o. Possible drug influences on systemic oxidative stress status in viv o were also investigated in subjects taking 50 mg captopril orally by measuring plasma and red blood cell peroxidation, as well as plasma pr otein thiols. 3 The results show that captopril is incapable of enhanc ing antioxidant properties of human plasma, of protecting it against s pecific oxidative attack and of decreasing systemic oxidant load in vi vo. 4 The present data, therefore, do not support the contention of a beneficial action of captopril through systemic antiradical-antioxidan t effects in human beings.