AIM: Angiotensin II has pro-fibrotic function in the liver. Blockade of the renin-angiotensin-aldosterone-system (RAAS) attenuates hepatic fibrosis. The aim of the present study was to determine the mechanism of angiotensinconverting enzyme inhibitor (ACEI) on the progression of rat hepatic fibrosis.

METHODS: Forty male Wistar rats were divided into three groups. Model group (Mo): The rats were injected subcutaneously with 40% of CCl4 0.25 mL/100 g. Perindopril group (Pe): The rats were injected subcutaneously with 40% of CCl4. Perindopril, equivalent to 2 mg/(kg• d), was administrated. Control group (Nc): the rats were treated with olive oil only. After 4 and 6 wk, the rats were killed. The liver sections were stained with Masson. The protein expressions of AT1R, TGF-β1 and PDGF-BB were examined by Western blot. Nuclear factor κB (NF-κB) DNA binding activity was examined by EMSA (Electrophoretic gel mobility shift assay). Matrix metalloproteinase-2, 9 (MMP-2, 9) activity was assessed by zymography. Serum laminin (LN) and hyaluronic acid (HA) were measured using radioimmunoassays.

RESULTS: Using Western blot, we clearly provided direct evidence for the expression of AT1R in liver. The expression was up-regulated when fibrogenesis occurred. Perindopril treatment significantly reduced mean fibrosis score, protein levels of AT1R, TGF-β1 and PDGF-BB, serum levels of HA and LN, and the activity of MMP-2, 9. NF-κB DNA binding activity markedly increased in model group, perindopril treatment considerably reduced NF-κB DNA binding activity.

CONCLUSION: Perindopril attenuates CCl4-induced hepatic fibrogenesis of rat by inhibiting TGF-β1, PDGF-BB, NF-κB and MMP-2, 9