Abstract
The ovaries of each 2 C3H mice of the age of 2 months or 12 months were observed by an electron microscope. In comparison of the findings on these controls, the effects of DMBA upon the ovarian tissues were investigated electron-microscopically. The 4 C3H mice, injected by 5 mg of DMBA-emulsion at the age of 45 days, were studied 7 days after the single injection. Some degenerative alterations in the mitochondrion, the polysomes and the smooth-surfaced endoplasmic reticula were detected on the ovum and the granulosa cells. Many dilatated ergastoplasms, coarse lipid granules and giant dense bodies could be found in the theca' cells and the interstitial gland cells. But, any changes were not demonstrated in the lutein cells. The ovaries of each 2 C3H mice, injected with 2.5 mg of DMBA-emulsion at the age of 2 months, were studied 2 or 5months after the single injection. Neither any ovum nor mature granulosa cells were detected in the ovaries. Some luteinizing sex-cord mesenchymal cells having both the tubular-structured mitochondrion and the small vesicular, smooth-surfaced endoplasmic reticula were seen in the abundunt collagenous stroma.
Pathological ovarian tissues of 13 old C3H mi ce, injected by 2.5 mg of DMBA-emulsion at the age of 52 or 59 days, were observed electron-microscopically 7-11.5 months after the single intravenous injection. In 3 cases of follicular type of granulosa cell tumor, more loose attachment of cytoplasmic membranes of tumor cells, nuclear and nucleolar predominances, abnormally dilatated rough-surfaced endoplasmic reticula, less polysomes, and decrease of the mitochondrion were indicated on the tumor cells. In 6 cases of diffuse type of undifferentiated granulosa cell tumor, the tumor cells indicated nuclear predominance, smaller vesicular smooth-surfaced ergastoplasms and spindle-shaped mitochondrion having some papillary cristae in their narrow cytoplasms. The polysome in them was less than the follicular granulosa tunir cells, but the rough-surfaced endoplasmi 'reticula were more detected in the tumor cells than inthe follicular granulosa tumor. In the focus of reactive cell proliferation accompanied by 1 ease of ovarian blood cyst, many electronmicrographs similar to the thecal cells were seen. Three cases of the atrophic ovaries revealed many luteinizing mesenchymal cells in the collagenous tissues. Electron-micrographs of the DMBA-induced ovarian tumors in C3H mice would indicate that the tumor cell of diffuse type of undifferentiated granulosa cell tumor is resemble to the undifferentiated sex-cord mesenchymal cells of the ovary, and that the tumor cell of follicular type of granulosa cell tumor is similar to the granulosa cells of growing follicles of the ovary.
