Effect of Adrenalectomy and Ovariectomy on Mammary Carcinogenesis in Strain C3H Mice

Abstract

A preliminary investigation to evaluate the relative importance of the ovarian and the adrenocortical secretions in mammary carcinogenesis in the mice is reported. 4-week-old C3H mice (female) were treated as follows: 1) untreated controls; 2) ovariectomized; 3) ovariectomized and implanted sc with 5-10 mg pellets of desoxycorticosterone acetate; 4) adrenalectomized and implanted with desoxycorticosterone acetate; and 5) adrenalectomized and ovariectomized and also implanted with desoxycorticosterone acetate. Animals were searched for tumors and the tumors and other relevant tissue were examined histologically. Results indicate that ovariectomy of 4-week-old C3H mice reduces the incidence of mammary tumors from 85 to 35%. Desoxycorticosterone acetate was insignificant in influencing the incidence of mammary tumors in ovariectomized mice. Adrenalectomized mice had a relative short survival time. Adrenalectomy reduced the incidence of mammary tumors to approximately the same extent as did ovariectomy. Ovariectomized-adrenalectomized animals had the lowest incidence of tumors. However significant demonstration would require larger numbers of animals. It is suggested that the effect of adrenalectomy is through the pituitary gland. Mammary tumors in mice deprived of their ovaries is probably due to extraovarian production of estrogenic compounds in the adrenal cortex.