The effect of corticotropin (ACTH) and streptomycin on experimentally induced pulmonary tuberculosis in rabbits.

The clinical evidence for the harmful effect of cortisone on patients infected with tubercle bacilli (American Trudeau Society, 1952; Fred et al., 1951; Traut and Ellman, 1952) has been supported by a series of laboratory studies on mice (Hart and Ress, 1950), rats (Cummings et al., 1952; Michael et al., 1950), guinea pigs (Spain and Molomut, 1950), and rabbits (Lurie et al., 1951). In the preceding study, it was shown that streptomycin could compensate for the deleterious effect of small but not large doses of cortisone. In this study corticotropin (ACTH) was administered to both primarily infected rabbits and rabbits previously sensitized. In contrast to the results with cortisone, corticotropin produced no deleterious effects on the animals when doses of 4 times the usual human therapeutic doses were employed. However, there was evidence of damage to the animals' resistance when doses 8 times the usual human dose were employed. Streptomycin prevented the harmful effect of the large doses of corticotropin. Since one of the purposes of this work was to compare the effects of corticotropin and cortisone on the tuberculous process, it was necessary to find some way of comparing the dosages of these two hormones to determine if they were physiologically of the same magnitude. Use was made of the lymphocyte depressing ability of corticotropin and cortisone (Dougherty and White, 1944, 1945) to accomplish this.