Histological studies on the effect of ACTH and flavin adenine dinucleotide on the rat adrenal cortex atrophied by hypophysectomy.

The present study describes the morphological changes in the adrenals of hypophysectomized rats injected 0.03 mg of ACTH and/or 10 mg of FAD intraperitoneally for 5 successive days starting 24 hrs after the operation. The administration of only FAD to intact or hypophysectomized rats showed no morphological change in the adrenal cortex. Simultaneous administration of FAD and ACTH to the hypophysectomized rats is more effective for preventing the atrophy induced than the administration of only ACTH. In these animals, similar morphological observations to those in the control, such as the increased nuclear volume, an increase of clear cells, diminuted numbers of lipid droplets and frequent occurrence of various types of granules, were obtained. FAD seems to be effective, through coexisting with ACTH, for preventing atrophy of the adrenals induced by hypophysectomy.