ACTH and Cortisone Aggravation or Suppression of the Febrile Response of Rabbits to Bacterial Endotoxin

Summary

(1) ACTH in divided doses of 15 mg per day and cortisone (5 mg per day) for 48 hours prior to the intravenous injection of a bacterial endotoxin (Shiga dysenteriae) and injection of 10 mg of either compound during the 2-day test period resulted in a significant lessening of the febrile response in the treated as compared to the control animals. (2) Rabbits given smaller doses of ACTH (5 mg per day) or cortisone (5 mg per day) for 24 hours prior to the injection of antigen, and continued through the test period, demonstrated an aggravated febrile and systemic response to the injected endotoxin as compared to the controls. (3) The significance of this time-dose relationship in the interpretation of experiments involving the use of ACTH and cortisone and bacterial endotoxins is discussed.