THE ROLE OF ALLOPURINOL IN PREVENTING OXYGEN-FREE RADICAL INJURY TO SKELETAL-MUSCLE AND ENDOTHELIAL-CELLS AFTER ISCHEMIA-REPERFUSION

One of the most important mechanisms in the production of ischemic dam age after replantation surgery is the rise of oxygen free radicals dur ing revascularization of ischemic tissues. Free radicals produce damag e in the cell membranes (lipoperoxydation). This occurs not only in mu scle tissue, but also in endothelial cells, with a consequent increase of local edema and the risk of compartment syndrome. This study attem pted to interrupt the ischemic-reperfusion injury process in ischemic rat hindlimbs. Complete ischemia was induced for different numbers of hours (3, 6, 9, 12 hr) in four groups of rats (24 animals in each grou p). Allopurinol, an oxygen free radical scavenger, was tested in solut ion, 12.5 mg/kg b.w., in half the studied animals (n = 12). Collected data showed an increase (mean value: 0.60 nM/mg at 3 hr; 0.90 nM/mg at 6 hr; 0.80 nM/mg at 9 hr; 0.89 nM/mg at 12 hr; mean value in nonische mic muscle = 0.526 nM/mg) in lipoperoxides INS between treated/untreat ed groups, p > 0.05) and high tissue pressure values in the posterior compartment of the ischemic rat hindlimbs. Allopurinol reduced the pre ssure values (p ( 0.05 in Groups 1-3; p < 0.1 in Group 4), but was not effective in reducing lipoperoxides in skeletal muscle.