Production of Androgens and Estrogens by Tubular Adenomas Which Developed in Ovaries of Mutant Mice of SI/SI^t Genotype¹ Free

Bilateral tubular adenomas develop spontaneously in ovaries of WB × C57BL/6 F₁-SI/SI^t mice after exponential loss of oocytes. We investigated the ability of this tumor to produce sex steroids. Incubation of tubular adenoma tissue with [³H] progesterone resulted in production of [³H]androstenedione and [³H]testosterone. The amount of androgens produced by the tumor tissue was much greater than that produced by the normal ovarian tissue. The concentration of testosterone in the serum of the SI/SI^t mice bearing tubular adenomas, measured by radioimmunoassay, was about five times as high as the value in the serum of the congenic +/+ mice. Although incubation of the tumor tissue with [³H]androstenedione resulted in production of ³H-estrogens, the aromatase activity of the tumor tissue was about one-fifth of that of the normal ovarian tissue. Therefore, the major sex steroid secreted by tubular adenomas seemed to be testosterone. These endocrinological features of tubular adenomas were consistent with the following pathological features of the SI/SI^t mice with the tumors: (a) although the weight of uterus of the SI/SI^t mice was about one-half of the value observed in the +/+ mice, it decreased markedly after oophorectomy; and (b) submandibular glands of the SI/SI^t mice were significantly heavier than those of the +/+ mice.