Abstract
ACTH·anti-ACTH immune complex was found to have steroidogenic activity, and to bind with rat adrenal frozen sections in a characteristic manner by means of immunofluorescence technique.
It specifically bound with the adrenal cortex, and competed with native ACTH, but not with insulin. The adrenal glands from hypophysectomized rats showed stronger affinity to the complex than the untreated. The outer zona fasciculata bound most prominently, and also occasionally the inner zona fasciculata and reticularis, but the zona glomerulosa never bound. The cellular sites of binding were not restricted on the cell membrane, but also cytoplasm of the cortical cells showed positive staining.
These binding characteristics of ACTH·anti-ACTH complex were discussed, comparing with those of ACTH receptor biochemically established.
