Effect Of Dexmedetomidine On Kidney And Myocardial Tissue Following Renal Ischemia-reperfusion In Rats

Objective:To observe the effect of dexmedetomidine(DEX) on kidney and myocardial tissue following different time of renal ischemia-reperfusion(I/R) in rats.Methods:Forty male Wistar rats,weighing 250-300g,were randomized into 5 groups(n=8 each)using a random number table:sham operation group(group S);3h reperfusion following ischemia 60min(group I/Rl);3h reperfusion following ischemia 120min(group I/R2);DEX+3h reperfusion following ischemia 60min(group D1);DEX+3h reperfusion following ischemia 120min(group D2).RIRI was induced by right nephrectomy and occlusion of the left kidney about 60min and 120min respectively followed by reperfusion in animals anesthetized with intraperitoneal chloral hydrate.At 30 min before ischemia,DEX 50ug/kg was injected intraperitoneally in group D1 and D2,and the rest procedures were similar to those previously described in group I/R1 and I/R2.Blood samples were collected at 3h of reperfusion to determine serum creatinine(Cr),blood urea nitrogen(BUN) concentrations.Kidney and myocardial specimens were removed for microscopic examination and IL-10,TNF-a content were detected by ELISA.ResultsCompared with group S,serum Cr,BUN concentrations and kidney tissue,myocardium IL-10,TNF-a content were significantly increased in group I/Rl,group I/R2,group D1 and group D2(P<0.05).Compared with group I/Rl,myocardium IL-10 content were significantly increased in group D1 (P<0.05)serum Cr,BUN concentrations and kidney tissue,myocardium TNF-acontent were significantly decreased in group D1(P<0.05).Microscopic examination showed that the pathological changes of both kidney tissue and myocardium were significantly attenualed in D1.Compared with group I/Rl,serum Cr,BUN concentrations and kidney tissue,myocardium IL-10,TNF-a content were significantly increased (P<0.05)and microscopic examination showed that the pathological changes of both kidney tissue and myocardium were significantly aggravated in group I/R2.Compared with group I/R1,kidney tissue,myocardium IL-10 content were significantly increased in group D1 (P<0.05),serum Cr,BUN concentrations and kidney tissue,myocardium TNF-a content were significantly decreased in group D2 (P<0.05).Microscopic examination showed that the pathological changes of both kidney tissue and myocardium were significantly attenualed in D2.Microscopic examination showed that the pathological changes of both kidney tissue and myocardium were significantly attenualed in D1.Conclusion:With the time of renal ischemia lengthing,pathological changes of both kidney tissue and myocardium were significantly aggravated,inflammatory factor levels increased.Effect of Dexmedetomidine can allenuate kidney and myocardial tissue injury following different time of renal ischemia-reperfusion in rats and inhibition of inflammatory responses maybe is involved in the mechanism.