Effect of Qizhi Jiangtang Capsule on the Ratio of Intima /media Thickness and Inflammatory Factors in Renal Small Artery of Diabetic Nephropathy Rats

Objective:To observe effects of qizhi jiangtang capsule on the ratio of intima /media thickness and inflammatory factors in renal small artery of DN rats.Methods:48 male Wistar rats were randomly divided into 5 groups(n=8) :the sham operation group,the model group,Valsartan group(control group),the low-dosage of qizhi jiangtang granules group(low dosage group) and high dosage of Qizhi Jiangtang granules group(high dosage group).Except the rats in the sham operation group,the other rats were established DN animal model by removal of the right kidney with intraperitoneal injection of STZ.Medicine was given to each group according to the designed concentration and dosage from 2 days of the model established.Urine protein quantitative,urine retinol binding protein(RBP),urinary N-acetyl-β-D-amino glucoside enzyme(NAG) and blood urea nitrogen(BUN),serum creatinine(Scr),β2-microglobulin(β2-MG) of DN rats were tested and recorded every 4 weeks.All animals were put to death after treated12 weeks.Histological change in the kidney tissues was examined by HE stain.Thickness ratio of intima/media of small artery in renal parenchyma were measured.Glomerular capillary ultrastructure was observed by electron microscopy.The expression of monocyte chemotactic protein-1(MCP-1) and renal arteriole CD31was detected by immunohistochemical.The expression of MCP-1 mRNA in renal tissue was detected in situ hybridization method,while the expression of α-smooth muscle actin(α-SMA) in renal arteriole was detected by immunofluorescence.Results:At all time points,TP、RBP、NAG of DN rats were significantly decreased by qizhi jiangtang capsule(P0.01),and renal function was improved in the low and high dosage groups.HE staining showed that renal and vessel pathological damage were lessened by qizhi jiangtang capsule.Comparison of thickness ratio of intima/media of small artery in renal parenchyma of each group showed that:the ratio of the model group was significantly higher than that of the sham operation group(P0.01),the ratio of the control group and the low-dosage group was significantly lower that of the model group(P0.05),the ratio of the high dosage group was significantly lower that of the low-dosage group(P0.01).Observations of electron microscopy show that thickening of glomerular basement membrane and mesangium hyperplasia were reduced by qizhi jiangtang capsule,the form of hole between the endothelial cells protected,podocyte foot process fusion reduced.Immunohistochemical tests show that the expression of MCP-1 and renal arteriole CD31were down-regulated by qizhi jiangtang capsule(P0.01).The expression of MCP-1 mRNA in renal tissue were down-regulated in situ hybridization method.while the expression of renal arteriole α-SMA were down-regulated by immunofluorescence test.Conclusion:Pathological damage of renal tissues and vascular structures was improved by qizhi jiangtang capsule in DN rats.This mechanism is partly related to the expression of MCP-1 and MCP-1 mRNA in the renal tissues were down-regulated,and inflammatory reaction was blocked.