Ischemia Preconditioning Is Mediated By Claudins Protects The Kidney Against Ischemic Reperfusion Injury In Mice

Objective To investigate the changes in expression and distribution of claudins in the process of acute kidney injury and confirmed that renal protective effect of ischemia preconditioning may be related to mediated by Claudins。Methods 1、Grouping:Two hundred and thirty male C57BL/6 mice were randomly divided into control group, sham operation group,model group,ischemic preconditioning group and sham preischemia group.all of groups except control group were divided into sub-groups according to reperfusion time(0h,3h,6h,12 h,24h,48 h,3d,5d,7d); 2、Animal Model:we clamped bilateral renal pedicle for 30 min to establish ischemia-reperfusion kidney injury model.sham group:only exposed bilateral renal pedicle not to clip and did nothing in the control group;ischemic preconditioning group reperfused after clamping bilateral renal pedicle for 15 min and establish ischemia-reperfusion kidney injury model according to the method. sham preischemia group mice only freed renalpedicle but not cliped,and establish ischemia-reperfusion kidney injury model after four days according to the methods. 3、Experimental Method:detecting the level of mice serum urea nitrogen and creatinine;HE staining test renal pathological damage;detecting cldn-2, and-10,-17 by RT-PCR and Immunohistochemistry;Results 1、Changs of kidney function and renal pathology score:Reperfusion after 30 min ischemia with the passage of time, Urea nitrogen, serum creatinine and kidney pathological grading gradually rose and reached peak at 24 hours, then gradually decreased; Expression tendency of groups in ischemia intervention groups were the same as model group, but were significantly lower than that of each of time in model group; 2、Changs of Claudin-2 expression: Claudin-2 m RNA and protein expression level in model group after reperfusion gradually reduced,fast from 6h and 24 h,and reahed the peak of 2.5 times the baseline value at the 24 h,then gradually recovered; The m RNA and protein expression level of Claudin-2 in ischemia intervention group were also slowly reduced, and reached the lowest at 24 h,then gradually increased,however,Claudin-2 expression level of each of time were higher than the same time in model group. 3、Changs of Claudin-10 expression: The protein and m RNA expression level of Cldn-10 in model group after reperfusion gradually decreased, and reached the lowest at 24 h,then gradually increased. The protein and m RNAexpression tendency of Cldn-10 in ischemia intervention group were same as model group,but the expression level were significantly higher at the same time point in model group. 4、Changs of Claudin-17 expression:The expression level of Claudin-17 in model group after reperfusion gradually increased,reaching the peak at the 24 h,and then gradually declined. Expression tendency of Claudin-17 in ischemia intervention group were same as model group,but the expression level were significantly lower at the same time point in model groupConclusion cldn-2、cldn-10、cldn-17 may participate in the lesion of kidney,and mediate renal protection mechanism of ischemic preconditioning...