Effects of antihypertensive treatment on cardiac IGF-1 during prevention of ventricular hypertrophy in the rat

There is some evidence that cardiac rather than circulating insulin-like gr owth factor-1 (IGF-1) levels contribute to the development of renovascular hypertensive left ventricular hypertrophy (LVH), remaining unknown the effe cts of antihypertensive drugs on IGF-1 levels. We have assessed here the pr eventive effects of enalapril, losartan, propanolol and a-methyldopa on lef t ventricle (LV) and circulating IGF-1 levels in a rat model of hypertensio n and LVH (Goldblatt, GB). Our results show that relative LV mass and the L V content of IGF-1 were significantly lower with all antihypertensive drugs in GB rats (p<0.001). Serum concentrations of IGF-1 were lower in GB rats treated with enalapril, a-methyldopa and propanolol (p<0.01), but not in th ose treated with losartan. These results support the hypothesis that local rather than seric IGF-I contributes to the development of left ventricular hypertrophy induced by pressure overload in the rat.