Expression of ZO-1 in the Kidney of Diabetic Rats and Benzapril Effects on it

Objective:To investigate the change of ZO-1 expression and the correlation between the podocyte number and ZO-1 expression,the effects of angiotensin converting enzyme inhibitor benzapril on the expression of ZO-1 protein and mRNA of diabetic glomerulopathy.Methods:STZ-induced diabetic rats were established.Immunohistochemistry and RT-PCR were employed to study the change of ZO-1 protein and mRNA.WT-1 was used to stain podocyte nuclei and investigate the change of podocyte number.Results:At week 8,the expression of ZO-1 protein decreased dramatically (P0.05);at week 12,it decreased more obviously(P0.01).The change of ZO-1 mRNA was similar to it immunohistochemical staining.At two time points,The podocyte number decreased dramatically(P0.05).At week 8,the expression of ZO-1 and podocyte number in benzapril group were higher than those in the diabetic group(P0.05);At week 12,podocyte number in benzapril group was higher than that in the diabetic group too(P0.01),but the change of ZO-1 expression had no statistical significance when compared with that in the diabetic group.The podocyte number was correlated positively with ZO-1(r=0.923,P0.01).The podocyte number was correlated negatively with urine protein(r=-0.95,P0.01).Conclusion:The expression of ZO-1 decreased in patients with diabetic nephropathy and was correlated positively with podocyte number.There was close relationship between the ZO-1 expression,podocyte number and urine protein.Benzapril can improve ZO-1 expression,decrease urine protein and then protecet renal function.