Possible role of nitric oxide in hepatic injury secondary to renal ischemia-reperfusion (I/R) injury.

Hepatic injury secondary to renal I/R injury has been documented in several studies. This study aimed to investigate the role of NO in hepatic injury secondary to renal I/R in rat model. Sprague-Dawley rats (n = 48) were divided into 4 equal groups; sham-operated, I/R injury group (45 min of bilateral renal ischemia), L-arginine group (I/R with 300 mg/kg L-arginine, 20 min before ischemia), L-NAME group (I/R with 50 mg/kg L-NAME, 20 min before ischemia). L-NAME (NO synthase inhibitor) caused significant elevation in serum creatinine, BUN, liver enzymes, liver histopathological damage score (p ≤ 0.05) and MDA production (p ≤ 0.001); on the other hand significantly decreased NO and GSH levels (p ≤ 0.05). L-arginine significantly decreased serum creatinine, BUN and GSH (p ≤ 0.05) and caused significant elevation in liver enzymes and NO (p ≤ 0.05), and also in MDA levels (p ≤ 0.001) in liver tissues. We conclude that endogenous NO might have protective effect against hepatic injury induced by renal I/R injury and inhibition of this endogenous NO by L-NAME or exogenous administration of NO (by L-arginine) might be harmful.