SUPPRESSION OF UTERINE GROWTH BY PURIFIED HYDROCORTISONE ACETATE, 9α-FLUOROHYDROCORTISONE ACETATE AND CORTICOTROPIN*†

Abstract

Hydrocortisone acetate, 9a fluoro-hydrocortisone acetate, and ACTH were tested against estradiol-17[beta] in an effort to ascertain their possible influence on uterine growth. The adult rats were bilaterally ovariectomized and one week later 0.1 [mu]g estradiol 17[beta] was injected subcutaneously daily for 3 days with each of the hormones named above. All compounds were injected at separate sites. Necropsies were performed 24 hours after the last injection; the uteri were quickly removed and wet and dry uterine weights were determined. Results obtained show that hydrocortisone acetate was more effective than cortisone in restricting the action of estradiol-17[beta] in uterine growth. The simultaneous administration of 0.1 [mu]g estradiol-17[beta] and 0.025 to 0.500 mg of 9[alpha] fluoro-hydro-cortisone acetate resulted in 10 to 90% restriction of uterine growth normally produced by 0.1 [mu]g estradiol-17[beta] alone; 0.3-2.5 mg hydrocortisone acetate was required for nearly comparable inhibition. ACTH (0,1-0.5 mg daily) effected 35-50% inhibition of uterine growth, but was without effect in estradiol -17[beta]-treated ovariectomized, adrenalectomized rats.