Sex differences in adrenocortical structure and function. VI. Long-term effect of gonadectomy and testosterone or estradiol replacement on rat adrenal cortex.

Gonadectomy or sham operations were performed on rats of Wistar strain weighing 150--170 g. Animals were sacrificed in groups, males 397 days and females 395 days after surgery. 14 days before autopsy some of the gonadectomized rats were injected with a single dose of depo-testosterone or depo-estradiol respectively. Absolute as well as relative adrenal weights were larger in female than in male rats. Long-term orchiectomy did not change these weights while testosterone, if compared with control, lowers the weights of the adrenals. Long-term ovariectomy lowers the weights of the glands and estradiol reversed them to the control level. Adrenal cortex of rats studied show irregular zonation. Within the zona fasciculata two types of cells were observed--with strongly eosinophilic and pale cytoplasm. In some cases groups of hypertrophied cells surrounded by spindle-shaped cells were observed. Neither long-term gonadectomy nor gonadal hormone replacement has a marked effect on the structure of the adrenal cortex. In male and female rats there was no difference in the volume of single zona fasciculata and reticularis cells. Long-term orchiectomy has no effect on this volume while testosterone resulted in a lowering of volume of zona fasiculata cells. Neither long-term ovariectomy nor estradiol has an effect on morphometric parameters studied in the fasciculata and reticularis zones. Distinct sex differences and dependence on sex hormones were found in reactions for alpha-glycerophosphate dehydrogenase and nonspecific esterases activity.