Hyperplastic and Early Neoplastic Changes in the Ovaries of Mice After Genic Deletion of Germ Cells<xref ref-type="fn" rid="FN2">2</xref>

Abstract

The spontaneous development of complex tubular adenomas in the ovaries of (C57BL/6J × C3H/HeJ)F1-WxWv hybrids was studied between the ages of 1 day and 22 weeks. The ovaries contained fewer than 1% of the normal complement of oocytes at 1 day of age. There was an exponential decrease in number of oocytes until none were present at 13 weeks. At 1 day of age the ovaries were composed predominantly of cords of pregranulosa cells. As the few oocytes and follicles surviving to sexual maturity grew, ovulated, and formed corpora lutea, interstitial cell hyperplasia, ingrowth of “germinal” epithelial tubules, and hyperplasia of the rete ovarii developed rapidly. By 8 weeks of age an intermixed proliferation of interstitial cells and “germinal” epithelial tubules began, accompanied by invasion of adjacent muscle, fat, and thin-walled vessels. The entire ovary was permeated and the diagnosis of complex tubular adenoma was made in 13 of 19 ovaries at 17 weeks, and in 19 of 20 ovaries at 22 weeks. Interstitial cells formed within granulosa cell cords, in the theca interna of atretic follicles, within degenerating corpora lutea, in the lining of the rete ovarii, directly from stromal cells, and in intimate association with “germinal” epithelial tubules. After the loss of the follicular apparatus, sex hormones continued to be produced in mice with ovaries containing hyperplastic interstitial cells.