[Free and protein-bound corticosterone levels of the plasma of white rats under hypoxia and after administration of adrenocorticotropic hormone].

It has been demonstrated that the plasma ratio of free and protein-bound corticosterone depends on the hypoxic degree. After two-hour hypoxia at an altitude of 10,000 m the trained and untrained animals exhibit a similar content of the free hormone (21%), with the content of total corticosterone being significantly lower in the trained rats. A study of variations in the content of free corticosterone in rats exposed to hypoxia for 20, 45 and 120 min and ACTH administration during the same time intervals has shown that the binding capacity of transcortine changes 45 min after the beginning of hypoxia.