Autoradiographic localization of angiotensin II binding sites in the brain, pituitary, kidney and adrenal gland of the rat.

In order to define more precisely the sites of action for circulating angiotensin II (ANG II) on its target organs, ANG II receptor sites were localized by in vitro autoradiography within the brain, pituitary, kidney and adrenal gland of the rat using [125I]-ANG II as the probe. [125I]-ANG II binding sites were seen in the anterior lobe of the pituitary, glomeruli and vasa recta of the kidney, the zona glomerulosa and medulla of the adrenals, and the subfornical organ and organum vasculosum laminae terminals of the brain. These result show that [125I]-ANG II can be used to label in vitro ANG II receptor sites and can further our understanding of the actions of ANG II in regulating arterial pressure and extracellular fluid volume.