Effects of benazepril and losartan on proliferation and collagen synthesis of cultured cardiac fibroblasts from SHR

Abstract

This study was to investigate the effects of angiotensin II (AngII), Benazepril (Bena) and Losartan on cell proliferation and collagen synthesis in cardiac fibroblasts (CFb). CFb derived from 12 wks old SHR (CFb SHR) and WKY (CFbWKY) were cultured by outgrowth of tissue block. Proliferation of CFb was measured by direct cell counting. Collagen synthesis was determined by 3H-proline incorporation. Data expressed as mean±SD of 5 determinations performed in triplicate. It was showed that in serum free (0.4% FCS) medium, Cell number of CFbSHR and CFbWKY was not significantly affected by AngII (10-10-10-6M) and Bena (10-9-10-5M). Increased 3H-proline incorporation of CFbSHR and CFbWKY was induced in a concentration dependent manner by Ang II (10-10-10-6M) in the presence of 0.4% FCS. The basal 3H-proline incorporation was 162% higher in CFbSHR than in CFbWKY(P<0.01). The increase in 3H-proline incorporation of CFbSHR and CFbWKY was 185% and 168% (P<0.01, respectively) in the medium containing 10-7 Ang II. 3H-proline incorporation of CFbSHR and CFbWKY induced by 10-7 Ang II in the presence of 0.4% FCS was inhibited by both Bena and Losartan in a dose dependent manner. It was suggested that collagen synthesis of both CFbSHR and CFbwky was promoted by Ang II and inhibited by Bena and Losartan.