OBJECTIVETo observe the effects of Fuzheng Huayu Recipe (FHR) on rat's renal interstitial fibrosis induced by mercuric chloride (HgCl2), and to explore preliminarily its mechanism of action.

METHODSRats were randomly divided into four groups: the normal group, the model group, the FHR group and the vitamin E group, the latter two were treated respectively by FHR 4.6 g/kg and vitamin E 100 mg/kg. Rats model was established by oral administration of 8 mg/kg HgCl2 for 9 weeks. Serum creatinine (Cr) and urea nitrogen (BUN) content were tested with corresponding test kits; hydroxyproline (Hyp) content in kidney was assayed with hydrochloric acid hydrolysis; renal histologic change was observed with HE, Masson and methenamine silver (PASM) staining; and collagen type I (Col I), as well as protein expressions of fibronectin (FN) and alpha-smooth muscle actin (alpha-SMA) was determined with Western blot.

RESULTSCompared with the model group, the kidney/body weight ratio, serum levels of Cr and BUN, kidney Hyp content, and severity of renal interstitial fibrosis in the two treated groups were significantly lower (P<0.05 or P<0.01), and the improvements were more significant in the FHR group than those in the vitamin E group; Col I and FN protein expression was also weaker in the two treated group (Col, P<0.05; FN, P<0.01); while the expression of alpha-SMA was lower in the FHR group (P<0.01), but it wasn't in the vitamin E group (P>0.05).

CONCLUSIONFHR could improve the HgCl2-induced renal function injury in rats, decrease extracellular matrix deposition and restrain renal interstitial fibrosis, the mechanism of action might be related with its inhibitory effect on myofibroblast activation.