Sex differences in adrenocortical structure and function. V. The effects of postpubertal gonadectomy and gonadal hormone replacement on nuclear-cytoplasmic ratio, morphology and histochemistry of rat adrenal cortex.

Studies were carried out on adult rats of Wistar strain. Six weeks after postpubertal gonadectomy some of the orchiectomized rats were injected with a single dose of testosterone cypionate and ovari-ctomized rats with estradiol cypionate (17 beta-cyclopentyloproprionate esters of testosterone or estradiol). The control rats were sham operated. Investigations were carried out 8 weeks after surgery. Absolute and relative adrenal weight is lower in the male than in the female rat. Orchiectomy increases these weights while testosterone restores them to their normal level. Ovariectomy has no effect on the weight of adrenal, estradiol, however, increases the relative weight of the gland. The adrenal cortex of the adult female is wider than in the adult male rat and in female gland sudanophobic zone is lacking. Orchiectomy leads to the broadening of the adrenal cortex and testosterone replacement has an opposite effect. Ovariectomy has no effect on the structure of adrenal cortex and estradiol replacement resulted in the narrowing of zona glomerulosa. There were no differences in the nuclear-cytoplasmic ratio of zona glomerulosa cells in male and Female rats and neither gonadectomy nor gonadal hormone replacement has no effect on this parameter. The nuclear-cytoplasmic ratio of zona fasciculata cells in the male is markedly higher than in female. Orchiectomy lowers this ratio and testosterone restores it to the normal level. Neither ovariectomy nor estradiol replacement has effect on the nuclear-cytoplasmic ratio of zona fasciculata cells. Similar changes as those in the zona fasciculata were observed in zona reticularis cells. Among the oxidoreductases studied, the most marked sex differences were found in alpha-glycerophosphate dehydrogenase activity. In control female rats an intense reaction for this enzyme is observed in broad band of cells of the zona fasciculata interna, while in male rats only individual cells showed this reaction. In orchiectomized rats the reaction for this enzyme is similar as in control female rats and testosterone restores it to normal. Ovariectomy has no effect on localisation of reaction while after estradiol replacement reaction was more intense. Regarding the remaining oxidoreductases studied, in the adrenal cortex of rats of both sexes no marked differences were observed in localization, however, intensity of reaction depended upon applied experimental conditions. More distinct sex differences were observed in topochemistry of some hydrolases and intensity of reaction depended upon the applied experimental conditions.