OBJECTIVETo study the effect of valsatan (angiotensin II receptor antagonist, AT1) on hepatocyte growth factor (HGF) in the airways and airway remodeling in asthmatic rats.

METHODSThirty two rats were randomly assigned into A-D four groups. Group A was normal control without treatment. Groups B-D were challenged by ovalbumin (OVA) for 2 weeks, 4 weeks and 4 weeks respectively to induce asthma. Group D received intragastric administration of valsatan (30 microg/kg daily for 4 weeks) after OVA challenge. The expressions of HGF, angiotonin II (AngII) and transforming growth factor (TGF-beta1) in the airways were detected by immunihistochemical staining. The pathological changes of airways were observed by Haematoxylin and Eosin staining.

RESULTSThe HGF expression of Group B was significantly higher than that of Group A (10.69 +/- 0.96% vs 5.49 +/- 1.34%; P < 0.05). Group C also showed an increased HGF level (11.85 +/- 0.87%) compared with Group A (P < 0.05). The HGF level in Group D (15.58 +/- 1.06%) was significantly higer than that of both Group B and Group C (P < 0.05). The expressions of TGF-beta1 and AngII increased with the challenged time, while valsatan treatment decreased significantly the levels of both. Valsatan treatment attenuated airway injuries of asthmatic rats induced by OVA sensitization/challenge.

CONCLUSIONSHGF has protective effects on airways and anti-fibrotic effects. Valsatan can improve airway remodeling possibly by increasing HGF levels in asthmatic rats.