The angiotensin II receptor will be purified from rabbit kidneys and antireceptor antibodies will be developed in goats. These antibodies will be used to identify the cellular and subcellular localization of the receptor; to establish whether the receptor molecules differ structrually in various anatomical locations; to characterize, at the molecular level, receptor participation in angiotensin-mediated, functional vascular changes; to characterize receptor participation in the pathogenesis of hypertensive models; and to intervene immunologically in the hypertensive process.