Study In Comparative Method Of Reducing Renal Ischemia-reperfusion Injury

Objectives:In this study, clamping the renal artery of the SD rats turns to renal ischemia-reperfusion injury(ischemia reperfusion injury, IRI) model, useing remote ischemic and preconditioning ischemia treatment(ischemic postconditioning, IPost C)、methods of inosine injection and HC-A renal protective perfusion treatment before and after reperfusion(remote ischemic preconditioning, RIPC), 24 hours, 48 hours, and 1 week after ischemia-reperfusion we detected blood urea nitrogen(BUN) and serum creatinine(Cr) in rat inferior vena. With histopathological wo can evaluate the degree of injury, and detective renal tissue myeloperoxidase(Myeloperoxidase, MPO), superoxide dismutase(Superoxide dismutase, SOD) activity and malondialdehyde(Malondialdehyde, MDA) activity to assess the extent of tissue peroxidation damage, comprehensive comparison of the protective effect of these types of treatment of renal IRI.Methods:Selection of adult female SD rats weighing approximately 220 ± 30 g, were randomly divided into sham operation group(Sham group), IR group, RIPC group, IPost C group, inosine injection treatment group(Inosine group) and HC-A kidney protective solution perfusion group(HC-A group). SD rats in each group open right kidney removed, occlusion of the left renal artery 45 minutes after the resumption of perfusion, and kidneys of renal artery pulsatility color changes, renal artery recovery pulse, kidney change color from dark red, indicating perfusion success. After the above treatment interventions reperfusion 24 hours, 48 hours and one week, rats were extracted under vena cava for serum Cr and BUN assess renal function. Left kidney removed, take part in renal tissue treated with liquid nitrogen cryogenic refrigerator into stored at-80 ℃, for the detection of renal tissue MDA, SOD and MPO activity. Another part of the kidney tissue placed in 4% paraformaldehyde solution, fixed for hematoxylin- eosin(HE) staining producer. Under an optical microscope, according to Paller scoring method, each slide choose five different perspectives, each field randomly selected 10 of tubular, with an evaluation of renal tubular epithelial cell damage. Statistical data analysis software SPSS 19.0, mean ± standard deviation() that the use of single-factor analysis of variance differences between comparison groups, P <0.05 was considered statistically significant. Results:1、Renal function evaluationReperfusion for 24 hours and 48 hours after, IR group、Post C group、RIPC group、inosine group、HC-A group and Sham group, the serum Cr were significantly higher(p <0.05); 24 hours after reperfusion, Post C group、RIPC group、creatinine group and HC-A group and IR group, serum Cr lower(p <0.05);IPost C group and RIPC group and HC-A group, serum Cr lower(p <0.05); 48 hours after reperfusion, IPost C group、RIPC group、inosine group and IR group and HC-A group, serum Cr lower(p <0.05); the IPost C group、RIPC group、inosine group and HC-A group was still lower of serum Cr than IR group after 1 week(p <0.05), no significant difference between the Sham group. 24 hours after reperfusion in IR group and HC-A serum BUN and Sham group was significantly higher(p <0.05); Post C group、RIPC group、creatinine group and HC-A group and IR group, lower serum BUN(p <0.05); Post C group and RIPC group than in HC-A serum BUN lower(p <0.05). 48 hours after reperfusion, IR group and IPost C serum BUN and Sham group increased(p <0.05), IPost C group, RIPC group and inosine group and IR group, lower serum BUN levels(p <0.05).2、Renal histopathologic examinationSham renal tissue morphology no obvious abnormalities, IR group and reperfusion 24 hours, severe structural damage kidney tissue after 48 hours, renal tubular epithelial cell necrosis, luminal expansion, seen a lot of dead cells; reperfusion 1 after weeks of mild renal tissue visible focal inflammation and spotty necrosis. IPost C group, RIPC group, inosine group and HC-A group of reperfusion for 24 hours and 48 hours later and IR group found that kidney tissue damage mitigation, renal tubular epithelial cell edema and mild to moderate bureaucratic expansion, cavity can be seen a little inflammation cell aggregation. 1 week after reperfusion renal tissue morphology recovered, partially visible tubules edema;3、Kidney tissue MPO activity24 hours after reperfusion, IR group, IPost C group, RIPC group, HC-A group and Sham group, renal tissue MPO activity was significantly increased(p <0.05); 48 hours after reperfusion, IR group, RIPC group, creatinine group and HC-A group compared with the Sham group, the renal tissue MPO activity increased(p <0.05); perfusion 24 hours and 48 hours after, IPost C group, RIPC group and creatinine group compared with the IR group, the renal tissue MPO activity was significantly lower(p <0.05);4、Kidney tissue MDA activityReperfusion for 24 hours and 48 hours after, IR group, IPost C group, RIPC group, inosine group, HC-A group and Sham group, renal tissue MDA activity was significantly increased(p <0.05); 24 hours after reperfusion, IPost C group, RIPC group, inosine group, HC-A group and IR group, renal tissue MDA activity was significantly lower(p <0.05); IPost C group and RIPC group and HC-A group contrast, MDA activity decreased(p <0.05); 48 hours after reperfusion, IPost C group, RIPC group and inosine group and IR group, MDA activity decreased(p <0.05).5、Kidney tissue MPO activityReperfusion for 24 hours and 48 hours after, IR group, IPost C group, RIPC group, inosine group, HC-A group and Sham group, the SOD activity was significantly reduced renal tissue(p <0.05); IPost C group, RIPC group, inosine group SOD activity and IR group comparison and HC-A group of kidney tissue is increased(p <0.05); 1 week after reperfusion, HC-A group and Sham group, SOD activity decreased(p <0.05).Conclusions:IRI renal pathology showed renal tissue cell structure and function abnormalities, Cr and BUN increased, MDA, MPO activity increased, SOD activity decreased; The results show, IPost C, HC-A kidney protective solution, RIPC and Inosine injection process and so it has a protective effect on renal IRI; it can reduce antioxidant mechanisms by MDA and MPO activity, improve SOD enzyme scavenging oxygen free radicals, etc., and to protect the effect of renal function. Studies show a protective effect RIPC on RIRI and and IPost C, no significant difference Inosine injection process, the more HC-A was treated for kidney protection RIRI more protective effect, because of its simple, non-invasive, effect clear advantages, so it has a broader clinical application.