Liver Cirrhosis Research Today is a free monthly online journal that collates and summarizes the latest research about Liver Cirrhosis, including details on alcohol, treatment, drugs, effects, causes.

The renin-angiotensin system in a rat model of hepatic fibrosis: evidence for a protective role of Angiotensin-(1-7).

Pereira RM, Dos Santos RA, Teixeira MM, Leite VH, Costa LP, da Costa Dias FL, Barcelos LS, Collares GB, Simões e Silva AC

Departamento de Pediatria, Faculdade de Medicina, Universidade Federal de Minas Gerais (UFMG), Av. Alfredo Balena, 190, Belo Horizonte, MG 30130-100, Brazil.

BACKGROUND/AIMS: The circulating renin-angiotensin system (RAS) [plasma renin activity (PRA), Angiotensin (Ang) I, Ang II and Ang-(1-7)] was evaluated in a model of hepatic fibrosis in rats. To investigate the pathophysiological involvement of Ang-(1-7), animals were treated with the Ang-(1-7) Mas receptor antagonist, A-779. METHODS: RAS components, liver function and histology were examined in male Wistar rats (220-300 g). Animals were submitted to sham-surgery or ligature of the bile duct and evaluated 1, 2, 4 and 6 weeks later. Blood samples were obtained to determine biochemical parameters and RAS components. A second group was treated with A-779 or vehicle to measure liver hydroxyproline and total transforming growth factor beta-1 (TGFbeta1). RESULTS: PRA and Ang I were significantly elevated in rats at 4 and 6 weeks compared to sham-operated animals. Ang II and Ang-(1-7) progressively increased over the 6 weeks. Changes in RAS profile correlated with histological signs of fibrosis and deterioration in liver function. Pharmacological blockade of the Ang-(1-7) receptor aggravated liver fibrosis with a significant elevation in hydroxyproline and total TGFbeta(1). CONCLUSIONS: Hepatic fibrosis was associated with RAS activation in our model. Our data also suggested that Ang-(1-7) played a protective role in hepatic fibrosis.

Published 19 March 2007 in J Hepatol, 46(4): 674-81.
Full-text of this article is available online (may require subscription).

© 2004-2008 Liver Cirrhosis Research Today. All Rights Reserved.