Expressions Of Podocin MRNA And Protein In Glomerulus Of Adriamycin-induced Nephropathic Rats And The Effects Of Drugs

Objective: To investigate the possible role of podocin in proteinuria and the effects of glicocorticoids and benazepril on the expressions of podocin mRNA and protein in Adriamycin-induced nephropathic rats. Methods: The rats were randomly divided into four groups (normal control group, nephropathy control group, glicocorticoids-treated group and benazepril-treated group). ADR(5mg/kg) was intravenously administered to the nephropathy group, while Saline was intravenously administered to the normal control group. Two weeks after the administration, the nephropathic model of 24-hour protein urine quantity> 30mg was formed. Prednisone (10mg/kg) and benazepril (3mg/kg) were orally administered to the glicocorticoids-treated group and the benazepril-treated group respectively. Four weeks after the administration, urinary protein and blood were checked and the rats were then killed to acquire the renal cortex from which the totle RNA and protein were drawn. The expressions of podocin mRNA and protein were measured with the semi-quantity RT-PCR and western blot. Results:The relative value of podocin protein in normal control group was 5. 26 1.19, there was not an expression of podocin protein in the nephropathy control group; glicocorticoids and benazepril could increase the expression of podocin protein. The relative values of podocin mRNA in the four groups (normal control, nephropathy control, glicocorticoids-treated and benazepril-treated groups) were 1.06 0.19, 1.96 0.98, 1.31 0.24, 2.46 1.49, respectively. The expressions of podocin mRNA in the nephropathy control group increased significantly in comparison with those in the normal control group (P<0.05). In comparison with the nephropathy control group, thegroup while increased significantly in benazepril-treated group (P<0.05). Conclusion:There was abnormity in expressions of podocin mRNA and protein in Adriamycin-induced nephropathic rats, the reduction of podocin expression is likely to be one of important facts in the production of proteinuria in Adriamycin-induced nephropathic rats. It is possible that glicocorticoids and benazepril have effects on nephrotic syndrome through changing the GBM molecule structure.