Effect of Valsartan on the expression of GLUT_1 and TGFβ_1in renal cortex of experimental diabetic rats

To investigate the mechanism of Valsartan in protecting the kidney of streptozotocin-induced diabetic rats Sprague-Dawley rats were randomly divided into diabetic model treated with valsartan[10mg/(kg·d)] group(A), non-treated diabetic model group(B) and normal control group(C). Plasma glucose,kidney mass/body mass ratio, serum creatinine, urinary creatinine and urinary albumin excretion rates were measured in the fourth and sixth week respectively. The expression of GLUT 1 and TGFβ 1 mRNA in renal cortical were measured with RT-PCR in the sixth week rats. Mean glomerular transverse sectional area and mean glomerular volume were calculated by analysis system of the image. In either two stages, kidney mass/body mass ratio,Ccr, 24 urinary albumin excretion rate in both diabetic group (B) were higher than that of normal group(C)(P0.01),but significantly decreased in group A than that in group B. Mean glomerular transverse sectional area and mean glomerular volume in A were significantly smaller than that of group B(P0.01). By the end of the sixth week,the expression of GLUT 1 and TGFβ 1mRNA of group B was significantly increased than that of group C in rat kidney cortex(P0.01), at the same time the expression of group A was decreased than that of group B(P0.05). The results showed that Valsartan could downregulat the expression of GLUT 1and TGFβ 1mRNA. It could also reduce the level of increasing rate of renal and urinary albumin and so was able to prevent the glomerular sclerosis.