Plasma ACTH in rats following medical adrenalectomy.

We have previously reported that surgically adrenalectomized nonstressed rats showed delayed secretion of the expected increase in plasma ACTH concentrations following adrenalectomy.(1) However, increased plasma ACTH concentrations were always detected when these animals were subjected to severe stress, and their responsiveness increased again seven days or more following surgical adrenalectomy. We are now reporting similar results which were obtained following prolonged systemic glucocorticoid administration (medical adrenalectomy) in similar groups of rats.