The ultrastructure of some histopathological changes seen in oviducts of mice continuously fed diets containing diethylstilbestrol.

Selected oviductal lesions associated with the continuous feeding of diethylstilbestrol (DES) were examined ultrastructurally Virgin female mice were fed diets containing 0, 320 and 640 ppb DES from 4 weeks of age. All animals reported on in this study were removed from the study and sacrificed for histopathological and electron microscopy examination when moribund and ranged from 622 to 762 days on the experiment. One oviductal change consisted of markedly vacuolated ciliated epithelial cells located primarily in the fimbria. Electron microscopy revealed that the large vacuoles were present throughout the cytoplasm of affected cells. These vacuoles were not lipid and appeared to be fluid-filled. No significant alterations in number or structure of cilia were observed. Since this alteration was seen in both DES and control animals, it may be age-related. A second kind of oviductal lesion consisted by enlarged secretory cells located predominantly in the isthmus. The cytoplasm of these cells consisted of extremely enlarged, dilated rough endoplasmic cisternae forming a subnuclear mass. Numerous primary and secondary lysosomes were seen in the apical cytoplasm between the cell membrane and nucleus. No evidence of a Golgi complex was seen. These alterations were seen only in DES-exposed animals and seem to indicate continued protein synthesis by the secretory cells but a deficiency in the packaging of this protein into secretory granules.