does the latter participate in the symptomatology of the steroid withdrawal syndrome and adrenal insufficiency?
The cytokines tumor necrosis factor-alpha (TNF alpha), interleukin-1 (IL-1), and IL-6 are secreted at inflammatory sites in tandem and play a crucial role in the inflammatory and wound-healing processes. All three cytokines are potent activators of the hypothalamic-pituitary-adrenal axis, through which they restrain inflammation, whereas IL-6 itself plays a role in the termination of inflammation as well. To test the hypothesis that endogenous glucocorticoids exert a negative tonic effect on the secretion of these cytokines, we studied 17 patients with Cushing’s disease and 2 patients with primary adrenal Cushing’s syndrome before and after surgery. Plasma TNF alpha, IL-1 beta and IL-6 were measured before surgery, while the patients were hypercortisolemic; on postoperative day 4 or 5, when they were hypocortisolemic; and on postoperative day 9 or 10, when they were receiving glucocorticoid replacement. During severe hypocortisolism, on postoperative day 4 or 5, plasma IL-6 levels rose