Angiotensin binding sites in the adrenal gland of the tree shrew

Abstract

Release of adrenal medullary catecholamines is under neuronal and humoral control. Among many factors, angiotensin II (All) has been proposed to play a modulatory role [1]. It induces release of catecholamines from the adrenal medulla [2], probably through action on specific All receptors [3]. By in vitro receptor autoradiography, high-affinity receptors have been demonstrated in the rat adrenal medulla using the All agonist 125I-[Sar1]-AII [4]. This ligand showed specificities similar to those of 125I-AII and cross-displacement in binding experiments. These characteristics made the [Sar1]-AII analogue a suitable ligand for All binding sites studies.