ABSTRACT
ObjectiveTo study the effect of 1,25-(OH)2D3 analogs paricalcitol on proteinuriaindiabeticnephropathy (DN)rats, andtoinvestigateitspossiblemechanism.Methods DN model rats were established by intraperitoneal injection with streptozotocin.All the DN rats were randomly divided into the paricalcitol group(group P ) and DN group(group D).Healthy rats were chosen as healthy control group(group N).24-h urinary protein and serum biochemical indicators were examined after 12 weeks.ELISA was applied to detect the level of renin and Ang Ⅱ in the kidney.Immunohistochemistry and real-time PCR were used to detect the protein and mRNA expression of heparanases(HPA)and podoein.Results Compared with group N,24-h urinary protein,serum creatinine,renin and Ang Ⅱ in group D and group P were markedly increased,and they were significantly higher in group D as compared to group P (all P＜0.05).Compared with group N,the expression of HPA protein and mRNA in group D and group P increased markedly,and higher expression was found in group D(all P＜0.05).The expression of podocin protein and mRNA in group D and group P decreased markedly,and lower expression was found in group D(all P＜0.05).Renin level was positively correlated with HPA protein expression (r=0.78,P＜O.OS),negatively correlated with podocin protein expression(r=-0.63,P＜O.05),and not correlated with their mRNA expression.Conclusion Paricalcitol can significantly reduce the proteinuria,which may be associated with the inhibition of renin by down-regulating protein expression of HPAin glomerular basement membrane and up-regulating protein expression of podocin in podocyte.