Effect of Enalapril or Lovastatin on Tubulointerstitial Injury Induced by Protein-overload Proteinuria in Rats / 대한신장학회잡지

ABSTRACT

BACKGROUND: Previous studies have demonstrated that enalapril or lovastatin seems to ameliorate the renal injury in several animal models with glomerulonephritis. The aim of this study was to examine whether enalapril or lovastatin was still beneficial in tubulointerstitial injury induced by protein-overload proteinuria in rats. METHODS: Enalapril(200mg/L in the drinking water) or lovastatin(16mg/kg, subcutaneously) was administered to uninephrectomized rats which received a daily intraperitoneal injections of bovine serum albumin(BSA, 1/100g body weight)(each n=6). Six rats were served as normal control. After 2 weeks, renal cortical pathologic findings, including immunohistochemistry for macrophage were examined and renal cortical osteopontin, MCP-1, endothelin-1, TGF-beta and procollagen alpha1(I) mRNA expression were examined by Northern blot analysis. RESULTS: Renal cortex in rats with protein-overload proteinuria showed infiltration of inflammatory cells including macrophages, tubular dilatation and atrophy. Renal cortical mRNA expression of osteopontin, MCP-1 and endothelin-1 were increased in rats with protein-overload proteinuria. There were no changes in TGF-beta and procollagen alpha1(I) mRNA expression. Enalapril decreased the macrophage infiltration significantly and inhibited the mRNA expression of osteopontin, MCP-1 and endothelin-1. However, lovastatin had no significant effects on the macrophage infiltration and cortical mRNA expression. CONCLUSION: Enalapril showed beneficial effects in tubulointerstitial injury induced by protein-overload proteiuria in rats by inhibition of macrophage infiltration and the cortical mRNA expression of osteopontin, MCP-1 and endothelin-1. However, lovastatin had no significant effects.