Ultrastructure of mouse uterine surface epithelium under different estrogenic influences: 6. Changes of some cell components

Abstract

The single injection of a short-acting estrogen into spayed mice initiated a process of growth which increased the amount and size of cellular components to a maximum at about 2 days after the administration of hormone. One exception was the number of microvilli, which was highest 4 hours after the injection of estrogen. Simultaneously, the thickness of the luminal surface membrane was decreased from about 70 A to about 40 A. The injection of a long-acting estrogen into spayed mice resulted in a process of secretion in the uterine epithelium. The ultrastructure of this epithelium was similar to that of the 2-day animals. Comparison with epithelium from spayed animals showed that the area of the luminal cell surface was about 50% larger in the cells of secreting animals. The ratio of area of Golgi region with vesicles and vacuoles to area with Golgi membranes increased about 2.5 times at the 2-day stage and during uterine secretion. The increase in the number of circular profiles was higher than the increase in the area with Golgi membranes. The number of profiles per square micron of the Golgi region was one half lower. The proportion of 0.06–0.12 μ large profiles in the zone 1 μ under the cell surface was changed from 25% to 54%. This was accompanied by an increase in density of the interior of the profiles.