Abstract
The responses of plasma cortisol and adrenocorticotropic hormone (ACTH) were examined to intravenous injection of recombinant bovine tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (INF-gamma) in Holstein cows. INF-gamma induced dose-dependent rises in the plasma levels of both cortisol and ACTH, while TNF-alpha induced comparable plasma cortisol responses with much smaller rises in plasma ACTH. The results suggest a direct stimulatory action of TNF-alpha on cortisol secretion from the adrenal gland in cattle.