Comparative Study On Protective Effects Of Three Kinds Of Preconditioning On Renal Ischemia Reperfusion Injury In Renal Interleaf Arterial

PartⅠComparison of protective effects of propofol,estrogen and ischemic preconditioning on renal ischemia-reperfusion injury in ratsObjective:To compare the protective effects of RIRI in rats with three pretreatments of propofol（Pro）,estrogen(_E2),and ischemic preconditioning（IPC）.Method:120 SD male rats were randomly divided into 6 groups with 20 in each group.Control group:No treatment was performed;Sham group:only right kidney was removed;Ischemia-reperfusion injury Group（I/R）:The right kidney of the rat was resected and the blood flow of the left renal artery was blocked for 45 min;the estrogen pretreatment group（E₂+I/R）:The rats were given intraperitoneal injection of estrogen（100 ug/kg）once a day for three days before surgery,and the rest were treated with I/R group;propofol pretreatment group（Pro+I/R）:The rats were given intraperitoneal injection of propofol（50mg/kg）once daily for three days before surgery,and the rest were in the same I/R group;the ischemic preconditioning group（IPC+I/R）:the right kidney of the rats was removed.In addition,blood flow to the left renal artery was blocked for 8 min.then it was re-instilled for 5 min and the blood flow of the left renal artery was blocked after repeated three times.The rest group were also in the same I/R group.After 6 h and 24 h,serum urea nitrogen（BUN）and creatinine（Cr）values were measured.At the same time,histopathological sections were stained with HE and evaluated by Paller.Result:（1）There was statistically significant in Serum BUN and Cr levels between Control group and Sham group comparison at two time periods in 6 h,24 h.In the I/R group,Serum BUN and Cr levels were obviously higher than the Control group（P<0.01）.Compared with the Control 6 h group,the levels of serum BUN and Cr in the IPC+I/R 6 h group,the Pro+I/R 6 h group,and the E₂+I/R 6 h group increased slightly,but there was no statistical significance（P>0.05）.（2）In our study,Renal HE staining did not show obvious morphological changes in 6 h and 24 h control groups comparison with the Sham group.The Paller score was also not statistically significant（P>0.05）.Furthermore,compared with the Control group,the renal tissue in the I/R group had significant pathological changes,and the Paller score was significantly higher than that in the Control group（P<0.05）.At each time point.the renal tissue damage was also observed in the IPC+I/R group,Pro+I/R group,and E₂+I/R group.Paller injury score was higher than that in the Control group（P<0.05）,but renal tissue Pathological changes were alleviated and Paller scores were significantly lower than those in the I/R group（P<0.05）.There was no significant difference betweend IPC+I/R 6 h group and Pro+I/R 6 h group（P>0.05）.The Paller score of Pro+I/R 24 h group was significantly higher than that of IPC+I/R 24 h group（P<0.05）.Conclusion:RIRI can cause renal pathological changes and renal function in rats,and E₂,Pro and IPC pretreatment have own protective effects on RIRI.Compared with the three pretreatment methods,E₂ has a strong protective effect on RIRI.Part Ⅱ Comparison and study of the effect of propofol,estrogen and ischemic preconditioning on the vasomotor function of renal interlobar artery in rats with renal ischemia reperfusion injuryExperiment 1: Comparison of the effect of propofol,estrogen and ischemic preconditioning on the vasomotor function of renal interlobar artery in rats with renal ischemia reperfusion injuryObjective: To study and compare the effects of propofol（Pro）,estrogen（E2）,and ischemic preconditioning（IPC）on the diastolic and diastolic function of interrenal artery vascular（RIA）after renal ischemia-reperfusion injury in rats.The effects of three pretreatments on renal ischemia-reperfusion injury were explored.Method: 120 SD male rats were randomly divided into 6 groups with 20 rats in each group: Control group: No treatment was performed;Sham group: Only right kidney was removed;Ischemia-reperfusion injury Group（I/R）: right kidney was removed and left renal artery was blocked for 45 minutes;estrogen pretreatment group（E2+I/R）: rats were given intraperitoneal injection once a day for three days before surgery Hormones（100 ug/kg）,others in the same I/R group;Prop I/R: rats were given intraperitoneal injection of propofol（50 mg/kg）once daily for three days before surgery.And the rest were in the I/R group;the ischemic preconditioning group（IPC+I/R）: the right kidney of the rat was removed and the blood flow of the left renal artery was blocked for 8 min and then re-instilled for 5 min.The left side was blocked three times.left Renal artery blood flow,the rest with the I/R group.After 6 h and 24 h,the interlobular arteries were dissected and the pressure-muscle test was performed.The systolic function of the interlobular arteries in each group was observed.Result:（1）Compared with the Control group,the RIA contraction rate of the Sham group had no significant change（P>0.05）at 6 h and 24 h.Compared with Control,the RIA contraction rate of I/R group was significantly decreased at 6 h and 24 h（P<0.01）.Compared with I/R group at 6 h and 24 h,the RIA contraction rate of Pro+I/R group,E2+I/R group and IPC+I/R group increased significantly（P<0.01）.Compared with E2+I/R group at 6 h and 24 h,the RIA contraction rate of Pro+I/R group was increased,but it was not statistically significant（P>0.05）.The RIA contraction rate was increased in IPC+I/R group.Statistically significant（P<0.05）.Compared with the Control group,the RIA contraction rate and rate of the E2+I/R 6 h group,Pro+I/R 6 h group,and IPC+I/R group were not statistically significant（P>0.05）,while E2+I/ R 24 h group,Pro+I/R 24 h group and IPC+I/R group had statistically significant differences（P<0.05）.（2）Compared with the normal control group,there was no significant change in the RIA contraction rate in Sham group at 6 h and 24 h（P>0.05）.At the 6 h time point,compared with the Control group,the RIA contraction rate in the I/R group was significantly lower（P<0.05）.Compared with the Control group,the contraction rate of the RIA in the IPC+I/R group was decreased.Statistical significance（P<0.05）,but no statistically significant difference in RIA contraction rates between E2+I/R group and Pro+I/R group;E2+I/R group,IPC+I/R,compared with I/R group The systolic rate of RIA in the group was significantly increased（P<0.05）.Compared with the E2+I/R group,the RV contraction rate in the IPC+I/R group was decreased,and the difference was statistically significant（P<0.05）.At the 24 h time point,compared with the Control group,the RIA contraction rates of the E2+I/R group,the Pro+I/R group,and the IPC+I/R group decreased,with statistical significance（P<0.05）;Compared with the I/R group,the contraction rate of the IPC+I/R group decreased,the difference was statistically significant（P<0.05）,there was no statistical difference between the Pro+I/R group（P>0.05）;and the Pro+I/R group.There was no significant difference in INR contraction rate between IPC+I/R 24 h group（P>0.05）.Conclusion: Renal ischemia-reperfusion injury caused a decline in systolic and diastolic function of RIA,but Pro,E2,and IPC preconditioning may play a protective role by improving RIA contraction rate and contraction rate,of which E2 is the most powerful.Experiment 2: Effects of propofol,estrogen and ischemic preconditioning on the vasomotor function of the rats’ renal interlobar arteries and Cx43 m RNA after renal ischemia-reperfusion injuryObjective: To study and compare the effects of propofol（Pro）,estrogen（E2）and ischemic preconditioning（IPC）on the expression of Cx43 m RNA in renal inter-vessel arteries（RIA）after renal ischemia-reperfusion injury in rats.To explore the mechanism of three preconditioning effects on renal ischemia-reperfusion injury.Method: 120 SD male rats were randomly divided into 6 groups with 20 rats in each group: Control group: No treatment was performed;Sham group: Only right kidney was removed;Ischemia-reperfusion injury Group（I/R）: right kidney was removed and left renal artery was blocked for 45 min;estrogen pretreatment group（E2+I/R）: rats were given intraperitoneal injection once a day for three days before surgery Hormones（100 ug/kg）,others in the same I/R group;Prop I/R: rats were given intraperitoneal injection of propofol（50 mg/kg）once daily for three days before surgery.And the rest were in the I/R group;the ischemic preconditioning group（IPC+I/R）: the right kidney of the rat was removed and the blood flow of the left renal artery was blocked for 8 min and then re-instilled for 5 min.The left side was blocked three times and left.Renal artery blood flow,the rest with the I/R group.After 6 h and 24 h,the interlobular artery was dissected.RT-PCR was used to detect the expression of Cx43 m RNA in the interlobular arteries of rats in each group.Result: There was no difference in Cx43 m RNA expression between Sham group and Control group at 6 h and 24 h（P>0.05）;The expression of Cx43 m RNA in I/R group,Pro+I/R group,E2+I/R group and IPC+I/R group was significantly higher than that in Control group（P<0.05）;Compared with I/R group,the expression of Cx43 m RNA in Pro+I/R group,E2+I/R group and IPC+I/R group was significantly decreased（P<0.05）.The expression of Cx43 m RNA in E2+I/R 6 h group was lower than that in Pro+I/R 6 h group and IPC+I/R 6 h group,but it was not statistically significant（P>0.05）.There was no significant difference in the expression of Cx43 m RNA between Pro+I/R 24 h group and E2+I/R 24 h group（P>0.05）,but the expression level of Cx43 m RNA in the IPC+I/R group was similar to that of E2+I/R group.Statistical significance（P<0.05）Conclusion: The increase of Cx43 mRNA expression in RIA after RIRI in rats suggests that the expression level of Cx43 m RNA in RIA may be related to renal ischemia-reperfusion injury.The protective mechanisms of Pro,E2,and IPC pretreatment may be related to the down-regulation of Cx43 m RNA expression in RIAs,with E2 down-regulating Cx43 m RNA expression levels in RIAs the most.Experiment 3: Effects of propofol,estrogen and ischemic preconditioning on the vasomotor function of the rats’ renal interlobar arteries and Cx43 expression after renal ischemia-reperfusion injuryObjective: To study and compare the effects of propofol（Pro）,estrogen（E2）and ischemic preconditioning（IPC）on the expression of Cx43 protein in renal inter-artery arteries（RIA）after renal ischemia-reperfusion injury in rats.To explore the mechanism of three preconditioning effects on renal ischemia-reperfusion injury.Method: 120 SD male rats were randomly divided into 6 groups with 20 rats in each group: Control group: No treatment was performed;Sham group: Only right kidney was removed;Ischemia-reperfusion injury Group（I/R）: right kidney was removed and left renal artery was blocked for 45 minutes;estrogen pretreatment group（E2+I/R）: rats were given intraperitoneal injection once a day for three days before surgery Hormones（100 ug/kg）,others in the same I/R group;Prop I/R: rats were given intraperitoneal injection of propofol（50 mg/kg）once daily for three days before surgery.And the rest were in the I/R group;the ischemic preconditioning group（IPC+I/R）: the right kidney of the rat was removed and the blood flow of the left renal artery was blocked for 8 min and then re-instilled for 5 min.The left side was blocked three times and left.Renal artery blood flow,the rest with the I/R group.After 6 h and 24 h,the interlobular arteries were excised and the expression of Cx43 protein in the interlobular arteries of rats was detected by Western-blot.Result: At 6 h and 24 h,the expression of Cx43 protein in RIA was not statistically significant between Sham group and Control group.The expression of Cx43 protein in the I/R 6 h group was significantly higher than that in the Control group（P<0.05）.The expression of Cx43 protein in IPC+I/R 6 h group was higher than that in E2+I/R group（P<0.05）.The expression of Cx43 protein in E2+I/R 6 h group,Pro+I/R 6 h group and IPC+I/R 6 h group was higher than that in Control group,but there was statistical significance（P>0.05）.The expression of Cx43 protein in E2+I/R 6 h group,Pro+I/R 6 h group and IPC+I/R 6 h group was significantly lower than that in I/R 6 h group（P<0.05）.The E2+I/R 6 h group was significantly different from the IPC+I/R 6 h group（P<0.05）,and there was no significant difference compared with the Pro+I/R 6 h group（P>0.05）.).There was no significant difference between Pro+I/R group and IPC+I/R group at 6 h and 24 h（P>0.05）.The expression of Cx43 in the I/R 24 h group was significantly higher than that in the Control group（P<0.05）.The expression of Cx43 protein in RIA of E2+I/R 24 h group,Pro+I/R 24 h group and IPC+I/R 24 h group was significantly higher than that of Control group（P<0.05）.The expression of Cx43 in RIA after 24 h RIRI in E2+I/R group was lower than that in Pro+I/R 24 h group,and the difference was not statistically significant（P>0.05）.The expression of Cx43 protein in RIA after 24 h RIRI in E2+I/R group was significantly different from that in IPC+I/R 24 h group（P<0.05）.Conclusion: The increase of Cx43 expression in RIA after RIRI in rats suggests that the expression level of Cx43 in RIA may be related to renal ischemia-reperfusion injury.The protective mechanisms of Pro,E2,and IPC pretreatment may be related to the down-regulation of Cx43 expression in RIA,with E2 down-regulating Cx43 expression levels in RIA the most.