Glycogen content in the adrenals and liver of rat embryos depending on the level of adrenocorticotropic functions.

The functional state of the adrenals of rats during prenatal development was studied. The accumulation of glycogen in the adrenals and liver in 15.5-21.5-day old embryos was used as the index. The maximum glycogen concentration in the adrenals and the minimum in the liver were detected in 15.5-16.5-day embryos, i.e., before the adrenals had begun to produce glucocorticoids. A sharp decrease in glycogen in the adrenals was observed in 17.5-day embryos, and an appreciable accumulation in the liver in 18.5-day embryos, which coincides with the beginning of the glucocorticoid function. Decapitation and encephalectomy performed at an age of 17.5-19.5 days of development of the embryos, were invariably accompanied by a significant increase in the glycogen content in the adrenals and a decrease in its level in the liver in the case of investigation after two days. This indicates an active participation of the hypothalamo-pituitary system in the regulation of the adrenocortical function in the late days of embryonic development.