Abstract: AIM: To explore the changes oflactic dehydrogenase (lDH)activity and theProtection ofl-arginine (l-Arg)on ischemia-reperfusion injury (HIRI)in rabbits.METHODS: Therabbitswere randomly divid-ed into three groups (n =7 in each):control group,0.9 %NaCl grouPandl-Arg group.Using a HIRI mod-el,the activities oflDH and superoxide dismutase(SOD)in serum and hepatic tissue,the contents of ma-londialdehyde (MDA),and nitric oxideProducts (NO₂/NO₃)levels were measured in rabbits.RESULTS: In 0.9 %NaCl group,lDH activity increasedProgressively-in serum (P<0.01),andlDH,SOD activities and NO₂/NO₃concentration decreased remarkably (P<0.05 orP<0.01),and MDA content increased signifi-cantly in hepatic tissue (P<0.01).These changes did not show inl-Arg grouP(P<0.05 orP<0.01).CONCLUSION: L-Arg shows aProtection on HIRI by decreasing oxygen free radicallevel and raising NOlevel.

Key words: pharmacology, hepatic ischemia-reperfu-sion injury, lactic dehydrogenase, L-Arginine, oxygen free radicals, nitric oxide, rabbits