In vitro and in vivo effects of UP 269-6, a new potent orally active nonpeptide angiotensin II receptor antagonist, on vascular smooth muscle cell proliferation.

1. The present studies were designed to measure the affinity of UP 269-6, a newly developed angiotensin AT1 receptor antagonist, for vascular AT1 receptors from normotensive and hypertensive rats and to investigate in vitro, its effects on angiotensin II (AII)-induced hyperplasia and hypertrophy of vascular smooth muscle cells (VSMC). In addition the in vivo effects of UP 269-6 on neointimal proliferation in a carotid artery balloon injury in normotensive rats were also investigated.