Cytogenesis in the rat adrenal cortex: evidence for an ACTH-induced centripetal cell migration from the zona glomerulosa.

The mechanism underlying cytogenesis in the adrenal cortex of ACTH-treated rats was investigated. ACTH was found to increase the number of parenchymal cells in the zona fasciculata as well as that of "S" phase cells in the inner half of the zona glomerulosa and in the outer third of the zona fasciculata. The fate of 3H-thymidine labelled cells in ACTH-administered rats was also autoradiographically followed. The results are consistent with the hypothesis that the ACTH-provoked hyperplasia in the zona fasciculata involves the centripetal migration of newly-formed parenchymal cells from the zona glomerulosa.