Ultrastructure of mouse uterine surface epithelium under different estrogenic influences: 3. Late effect of estrogen administered to spayed animals

Abstract

Spayed mice of the C3H strain were given a single intraperitoneal injection of 1 μg estradiol-17β in 0.05 ml propylene glycol. The appearances of the uterine epithelial cells were investigated 2, 4, and 6 days after the administration of hormone. The vaginal smears were cornified 2 days after injection, but the folding of the lateral cell membranes, the intercellular vacuoles, the intramitochondrial bodies, and the vesicles, present in estrous mice, were not observed. After the 2-day stage the epithelial cells gradually returned to the castrate condition. The cell height changed from about 16 μ to 9 μ. The microvilli decreased in number and length, and the lumenal substance, which was observed in animals 2 days after hormone injection, was not present at the later periods. The distances between the two dense layers of the lumenal cell surface and between the lateral, adjacent cell surfaces, which decreased during the day after estrogen administration, returned to the castrate level 2 days after injection. The mitochondria of the 4-day animals were longer than those of spayed animals, but 6 days after estrogen injection they were small and had a rounded or rod-shaped form. No differences in ultrastructure of the uterine epithelia from treated animals and spayed animals remained 6 days after estrogen injection. The change in number of lipid granules was accompanied by the appearance of areas with granules, membranes, and spaces. Many cytoplasmic bodies of different shapes and sizes were observed in the neighbourhood of these areas.