Ultrastructural changes of sebaceous glands in castrated and testosterone-treated male rats. A qualitative and quantitative study.

The effect of testosterone on the sebaceous gland was studied in the male rat. Biopsies of dorsal skin from intact rats, from rats four weeks after castration, and from castrated rats treated with testosterone propionate for three weeks at a dose of 250 micrograms/kd/day (s.c.) were examined by electron microscopy. In the treated animals intermediate sacrifices were performed on days 4, 7, 14, 21. Stereology was used for a morphometric analysis of the smooth endoplasmic reticulum (SER). The presence of a vesicular endoplasmic reticulum throughout the cytoplasm of differentiating cells was observed in the sebaceous glands of intact rats. Following castration there was a shrinkage of these cells and a striking decrease in the volume density of the endoplasmic reticulum vesicles. The administration of testosterone to gonadectomized rats resulted in an increase in vesicle content above the normal level from the first week as revealed by stereological analysis. This study confirms the trophic effect of the androgen on the sebaceous gland at a subcellular level. Furthermore, it is shown that stereology is a useful method for detecting early hormone-induced changes and could be valuable for studying the effects of anti-androgens on this gland.