Effects of valsartan on adrenomedullin receptor expression in diabetic rat's renal cortex / 解放军医学杂志

ABSTRACT

Objective Valsartan, the angiotensin Ⅱ type 1 receptor blocker, is recently proved to reduce urinary albumin at the microalbuminuria stage in human diabetic nephropathy without altering glucose metabolism. But the pathway is still uncertain. In present study, we examined the changes of adrenomedullin receptor (ADMR) mRNA and protein expressions in the renal cortex of diabetic rats to investigate the protective effects of valsartan on an experimental model of diabetic renal injury. Method The SD rats were randomly divided into following groups normal rats, STZ-induced diabetic rats, and diabetic rats treated with valsartan. STZ-induced diabetic rats were treated with valsartan (10mg/kg body weight) or vehicle for 8 weeks. The expressions of ADMR mRNA in renal cortex were analyzed by RT-PCR, as well as ADMR protein expressions were detected through western blot. Results We found (1) Valsartan treatments reduced urinary albumin excretion in 24h, compared with the untreated. But no notable difference was seen in HbA1c and blood sugar of diabetic rats between the two groups. (2) Valsartan treatments increased the expressions of ADMR mRNA and protein in diabetic rats renal cortex. Conclusion These results indicate that valsartan treatment can upgrade the expressions of ADMR in the renal cortex of diabetic rats. It may be one of renal protective pathways of Ang Ⅱ type 1 receptor blocker.