The displacement of [125I]Sar1, Ile8 angiotensin II binding by the receptor subtype selective angiotensin II antagonists, DuP-753 and WL-19 (PD121981) was used to define the relative proportion of angiotensin subtype AT1 and subtype AT2 receptors, respectively in various tissues (aorta, heart, adrenal cortex, kidney cortex and brain) of the rat, rabbit and monkey. The relative abundance of these receptor subtypes varied greatly not only among different tissues of the same species but also within the same tissue of different species. The relative affinity of the DuP-753 and WL-19 for the angiotensin receptor subtypes did not vary markedly suggesting that the two angiotensin receptor subtypes in these tissues and species are similar.