Research on the protective role of remote ischemic preconditioning in kidney ischemia reperfusion injury

Objective To investigate the protective effects and underlying mechanism of remote ischemic preconditioning (RIPC) in kidney ischemia reperfusion injury (IRI). Methods Sprague-Dawley rats were randomly divided into three groups following right-side nephrectomy: Sham-group, IRI-group, RIPC-group. At 24 h after reperfusion, the blood samples, renal tissues and urine were collected. The degree of renal injury was evaluated by serum creatinine (SCr), blood urea nitrogen (BUN) and histological score. We also detected the expression of cyclooxygenase-2 (COX-2), membrane associated prostaglandin E synthase-1 (mPGES-1) and prostaglandin E-2 (PGE2). Results Rats treated with RIPC before ischemia revealed significant improvements in renal function (P value is 0.031 and 0.004 respectively) and morphology (IRI: 3.63±0.54, RIPC: 2.44±0.66, P=0.001). The results derived from immunohistochemistry revealed that the content of COX-2 and PGE2 were obviously decreased in RIPC group than those in IRI group (P value is 0.000 and 0.034 respectively), however, the expression of mPGES-1 remained no significant change (P=0.367). Conclusion The results suggested that RIPC could attenuate renal IRI and improve kidney function. The COX-2/PGE2 pathway may play a critical role in this process. Key words: Remote ischemic preconditioning; Ischemia reperfusion injury; Cyclooxygenase-2