OXYGEN-FREE RADICALS IN EYRTHROCYTES DURING OPEN-HEART OPERATION

This study was performed to observe the effect of myocardial ischemia on the patients undergoing cardiopulmonary bypass (CPB) operation. For this aim, superoxide dismutase (SOD) activities, reduced glutathione (GSH) and lipid peroxide (LP) levels were determined in blood samples which were obtained from the coronary sinus. Sampling times were as fo llows: (1) Before CPB. (2) Immediately after CPB. (3) Fifteen minutes after the second specimen. (4) Thirty minutes after the second specime n. SOD activities of these groups were 5135.10 +/- 278.51 U/g Hb, 3505 .64 +/- 302.09 U/g Hb, 4206.55 +/- 272.25 U/g Hb, 4707.20 +/- 270.91 U /g Hb respectively. Also the LP levels were 1.90 +/- 0.29 nmol MDA/ml, 4.37 +/- 0.52 nmol MDA/ml, 4.09 +/- 0.39 nmol MDA/ml, 2.74 +/- 0.30 n mol MDA/ml respectively. GSH levels were slightly increased during isc hemia and reperfusion; 103.27 +/- 5.18 mg/dl, 125.00 +/- 10.36 mg/dl, 125.00 +/- 6.61 mg/dl, 111.18 +/- 8.22 mg/dl respectively. SOD activit ies were reduced significantly in second group (p < 0.001), in third a nd fourth groups (p < 0.01) as compared with control group. Also LP le vels were increased significantly in all groups (p < 0.001) as compare d with controls. Our results confirm the generation of oxygen free rad icals from ischemia and reperfusion of heart during CPB. Also it appea rs that oxygen free radical generation exceeds the capacity of intrace llular SOD, which is the most important scavenger of free radical in t he cell.