Protection of Adrenalectomized Animals Against Bacterial Intoxication.

Abstract

In 1924, Scott 1 first showed the greatly reduced resistance of animals with latent adrenal insufficiency to intoxication by pyogenic bacteria. Numerous attempts to protect with cortical extract against this fatal effect were carried out unsuccessfully, the difficulty being to get rid of epinephrin without destroying the active cortical hormone. Recently Scott and Bradford 2 found some increased resistance to bacterial intoxication conferred by the administration of a cortical extract (Swingle and Pfiffner 3 ). A difficulty in this experiment was that no satisfactory criterion of adequate substitution was available. In the present work the growth curve is used as an indication of adequate dosage of the cortical hormone. 4 As the function of the adrenal cortex to protect against the harmful effects of bacterial intoxication is important in clinical medicine, we have tried to prove beyond any doubt that an extract of the adrenal cortex offers such protection.

The growth curves of 32 young adult male rats were determined for 2 weeks. Both adrenals were then removed at one operation. The animals were divided into 2 groups of 16 each. All were injected with the same volume of fluid and were weighed daily. The animals of Group A were injected with cortin obtained by the ether-alcohol method, 5 those of Group B with isotonic saline. The extract used in the first week was prepared by a new method which was found to greatly reduce its potency. Two rats in each group died in this interval. A potent extract was used after the first week, under the influence of which the weight curves of the extract-injected animals recovered their preoperative slope. The product from 25 gm. of cortex was injected twice daily in each rat in Group A.