Protective effect of ETaR siRNA on renal ischemia-reperfusion injury in rats by changing the immuno-microenvironment of kidney

Objective To explore the protective effect of ETaR siRNA on renal ischemia reperfusion injury (IRI) by changing the immuno-microenvironment in rats. Methods A total of 40 male Sprague-Dawley (SD) rats were randomized into four groups of sham, IR, negative siRNA and ETaR siRNA. A renal IRI model was generated by clamping left renal artery. ETaR siRNA was delivered into kidney through renal vein by a retrograde 'hydrodynamic’ injection. Blood samples were collected for detecting renal function and kidney tissue harvested for Hematoxylin & Eosin (HE) staining, TdT-mediated dUTP Nick-End Labeling (TUNEL) staining, polymerase chain reaction (PCR) and Western blot at 48 h post-reperfusion. Results Serum creatinine, blood urea nitrogen and renal apoptotic cells increased and renal tissue was injured after IR. The changes were inhibited by ETaR siRNA. PCR showed that ETaR siRNA treatment significantly down-regulated the expressions of inflammatory factors TNF-α, IFN-γ and IL-6 and transcription factor NF-κB induced by IR. Conclusions ETaR siRNA can effectively improve the immuno-microenvironment and thereby alleviate renal ischemia reperfusion injury. Key words: Rats; Kidney; Endothelin receptor; Small interfering RNA; Immuno-microenvironment; Reperfusion injury