Effects of Recombinant Adenovirus Hepatocyte Growth Factor Gene on Myocardial Remodeling in Spontaneously Hypertensive Rats

Background and Objectives: Myocardial hypertrophy and fibrosis are important determinants of congestive heart failure. Previous work has shown that hepatocyte growth factor (HGF) can reduce acute myocardial injury and tissue fibrosis. This study was designed to examine the effects of HGF on myocardial remodeling following sustained hypertension. Methods and Results: There were 4 experimental groups (n = 6) that included spontaneously hypertensive rats (SHRs) injected with 0.1 mL of adenovirus (Ad)-null into the left ventricular (LV) free wall, SHR injected with 0.1 mL of Ad-HGF gene (5 x 10(9) pfu/mL), and SHR injected with 0.1 mL of normal saline, and Wistar Kyoto rats injected with 0.1 mL of Ad-null served as control. At 4 weeks after injection, rats were sacrificed, and HGF expression, myocardial fibrosis, and LV function were determined. We observed that HGF protein expression was reduced in the hearts of SHR (P < .05 vs normal control) and it was markedly increased in SHR injected with Ad-HGF (P < .01 vs SHR injected with Ad-null). Myocardial fibrosis, collagen I, LV mass index (LVMI), and LV end-diastolic pressure (LVEDP) were increased and -dP/dtmax was decreased in SHR injected with Ad-null or normal saline (P < .01 vs normal control). Upregulation of myocardial HGF expression in SHR significantly suppressed myocardial fibrosis, collagen I content, LVMI, LVEDP, and increased -dP/dtmax (all P < .05 vs SHR-Ad-null, n = 6). Conclusions: These findings indicate that HGF expression is attenuated in hypertrophic and fibrotic myocardium of SHR. The forced increase in HGF exerts a salutary effect on myocardial fibrosis, collagen I expression, and hemodynamic parameters.