Histological responses of the alternative or combined administrations of ACTH and GH to adrenal cortex

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The hypophysectomized rats of Wistar strain receiving an operation in 60-90th postnatal day respectively were injected with ACTH and GH alternatively or in combination. The adrenal cortex of these animals was histologically examined in comparing it to that in control hypophysectomized rats and the results were as follows : A decided conclusion was not obtained as to the changes in weight of adrenal cortex, since the number of experimental animals was small, and the value presented was complicated with the animal difference. But the organ body weight ratio shows that the adrenal gland surely decreases in weight by the hypophysectomy, but cannot be recovered from the reduction by means of the maintenance test of ACTH (2.5 mg/day for 7, 10 days) or GH (2 mg/day for 7 days), and of the repair test of ACTH (the same dose for 5 days) or ACTH and GH in combination (the same dose for 5 days), begun from the 6th day after the removal. Therefore ACTH and GH would be uneffective to allow the animals to recover the loss of organ weight, so far as this admistration method is concerned.However, it was informed in present research that the hormones are able to modify the histological changes induced by the hypophysectomy. The control hypophysectomized rats (7th day) provided the partially broadened zona glomerulosa in which the cells containing a lot of fat granules arrange fascicularly without a formation of glomerulum. The transitional zone became thicker, representing a layer of the package of nuclei. The cell-strands in zona fasciculata were irregular in general, slender, anastomosed one another and atrophic in some degree. Their cell-bodies were submitted to be rich in fat granules instead of proteinic stainable granules. The cortex cells at the vicinity of medulla surrounded by the multiplied connective tissue were usually flat in shape. The finding in the 10th day after the removal resembled in many respects that of the 7th day, but tended to be shown as the more pronounced changes. When the hypophysectomized rats were administered for 7-10 days with ACTH, the zonation of adrenal cortex was precisely altered, although the whole thickness of it was not recovered. The elongation of cell fascicules in zona fasciculata presses the zona glomerulosa on the capsule. The disappearance of the transitional zone resulted in the mutual transformation between atrophic zona glomerulosa and broad zona fasciculata, where the former no longer consisted of independent glomeruli. The superficial area of adrenal cortex was scanty of fat granules, whereas full of stainable granules (stained with iron-hematoxylin). Despite the atrophic pattern and irregularity of fasciculata cell-strands was not restituted by the administration of ACTH, it was fairly demonstrated that the gross fused fat droplets decreased in number within the cellbodies, in addition the stainable granules increased. This fact may show that the improvement in the internal cell stracture fellow the replacement therapy. Also the connective tissue near the medulla became thoroughly indistinct. As above mentioned, ACTH is expected to have the sweeping ability of some obstacles in intracellular hormone synthesis by the hypophysectomy, and at least the changes by ACTH was akin, beyond the recovery, to the pattern of elevation in function of cortical cells, as is seen in intact rats exposed by the stressful stimuli.The repair test by ACTH showed the same improvement as by its maintenance test. Of course, the betterment may be restricted to zonation and cell internal structures in connection with the metabolic amelioration, but was not involved in the hyperplasia of cotical cells.In the event of repeated injections of GH for 7 days (maintenance test) to the hypophysectomized rats, the symptom of the ablation is almost irrecoverable. The changes is not utterly reconcile with the findings of hypophysectomized untreated group,