Protective effects of L-arginine on experimental myocardial injury inducedby beta-adrenergic stimulation in rats

Changes in the activities of lysosomal enzymes (beta-D-galactosidase, beta- D-glucosidase, beta-D-N-acetyl glucosaminidase, and beta-fucosidase), mitoc hondrial enzymes (isocitrate dehydrogenase, malate dehydrogenase, succinate dehydrogenase, alpha-ketoglutarate dehydrogenase, and NADH dehydrogenase) and marker enzymes of cardiac function (LDH, AST, ALT, and CK) during isopr oterenol-induced myocardial infarction and the effect of L-arginine pre-tre atment were studied in male albino rats. In the rats given isoproterenol, t here were significant increases in serum activities of LDH, CK, AST, and AL T and significant reductions in the myocardial tissue. Activity of the lyso somal enzyme beta-D-N-acetyl glucosaminidase was considerably increased, an d beta-galactosidase was considerably decreased in the isoproterenol-treate d rats as compared with that in those given isoproterenol after pre-treatme nt with L-arginine. The activities of the mitochondrial enzymes in the isop roterenol-intoxicated group were significantly lower as compared with those of the L-arginine supplemented rats given isoproterenol. These results con firm the efficacy of L-arginine as a potent cardioprotective agent and the protective effect of L-arginine against isoproterenol-induced mitochondrial and lysosomal damage.