Renoprotective effect of azelnidipine in rats

Abstract

To assess whether azelnidipine (AZN) exerts renoprotective effects, 20-week-old adult male stroke-prone spontaneously hypertensive rats (SHRsp) were treated with AZN 10 mg/kg/d (n=6), olmesartan (OLM) 3 mg/kg/d (n=4), hydralazine (HYD) 20 mg/kg/d (n=3), or water (control; n=5). Each test agent was administered by oral gavage for 12 weeks. Systolic blood pressure (SBP) was measured every 2 weeks and urinary protein excretion (UproV) every 3 weeks. At the age of 32 weeks, the rats were sacrificed and blood and kidneys collected for biochemical, histological, and immunohistochemical studies. All drug treatments significantly (p<0.05) reduced SBP, UproV, and blood biochemical parameters such as creatinine, total cholesterol, and blood urea nitrogen. Masson trichrome staining and immunohistochemical staining revealed significant (p<0.05) reductions of interstitial fibrosis, collagen type III, nicotinamide-adenine dinucleotide/nicotinamide-adenine dinucleotide phosphate oxidase, and p22phox and p47phox components expression in the AZN- and OLM-treated groups in comparison with rats treated with HYD and control animals. ED1, 4-hydroxy-2-nonenal (4-HNE), and heat shock protein (HSP)-47 expression was also reduced in the AZN- and OLM-treated groups versus in HYD and control animals. These results indicate that not only OLM but also AZN exerts renoprotective effects through inhibition of macrophage infiltration and antioxidant activity in SHRsp model of renal injury. © 2008 Pharmaceutical Society of Japan.