Rat brain aDd pituitary angiotensin¡ II (AII) binding sites were quaptitated by incubation of tissue s€ctioos \\itb r¡I-[Sarl]-AIl, ultro film radioautography, computerized densitrometry, and comparison wirh ¡25l-standards at appropriate film exposüre times. The highest numbcr of AII binding sircs wai found in antcrior pituitary, and thc circunventricular organs, organon subfomicalis and organon vasculosum laminae terminalis.