[The effect of experimental thyrotoxicosis on the state of the hypothalamo-hypophyseo-adrenal system in rats].

Experiments were conducted on male albino rats (298); a study was made of the effect of experimental thyrotoxicosis of various severity on the state of the hypothalamo-hypophyseal-adrenal system. It was found that the hypothalamo-hypophyseal-adrenal system responded differently to the excess of thyroid hormone, depending on the strength and duration of action. Mild thyrotoxicosis was accompanied by its activation expressed in increased CRF of the hypothalamic extracts, a reduction of the ACTH in the hypophysis and a fall of ascorbic acid content in the adrenal glands. Severe and prolonged thyrotoxicosis was accompanied by a depression of the hypothalamo-hypophysio-adrenal system function. It was concluded that the action of thyroid hormones on the CRF secretion served as the leading mechanism of the mentioned reactions.