A protective effect of glucocorticoids in hypoxic stress.

ROOSEVELT, T. STEVEN, ANN RUHMANN-WENNHOLD, AND DON H. NELSON. A protective e$ect of glucocorticoids in hypoxic stress. Am. J. Physiol. 223(l) : 30-33. 1972.-Studies were carried out in female rats on the effects of glucocorticoids on survival time and lactic acid formation in hypoxic stress. Endogenous corticoids increased survival time of rats exposed to a hypoxic (5% 0,) atmosphere, since sham-adrenalectomized animals survived significantly longer than adrenalectomized controls. Administration of cortisol had a similar effect in adrenalectomized rats. The difference in survival time is probably not due to the absence of the adrenal medulla, since sham-hypophysectomized rats survived hypoxia significantly longer than hypophysectomized rats. Blood lactate was elevated in hypoxic animals but, more significantly, intact animals had lower levels of blood lactic acid than adrenalectomized animals. Animals replaced with cortisol following adrenalectomy also had lower levels of blood lactate following exposure to hypoxia than adrenalectomized controls. Corticoids probably protect against hypoxia through a facilitation of aerobic metabolism.