Sex differences in adrenocortical structure and function. XV. Cellular composition and quantitative ultrastructural study of adrenal cortex of adult male and female hamster.

Cellular composition of adrenal cortex of adult male and female hamster was evaluated and parallel quantitative ultrastructural studies were performed. The adrenal cortex of adult male hamster contained more parenchymal cells than that of female and the difference depended mainly upon the number of the zona glomerulosa and zona fasciculata cells. Moreover, cells and nuclei of the zona reticularis were markedly larger in male animals. Ultrastructural observations of both male and female adrenal glands did not reveal any significant difference; however, stereology showed that the volumes of mitochondrial compartment and membrane space, as well as the surface areas of mitochondrial cristae and smooth endoplasmic reticulum tubules were significantly higher in the male hamster zona reticularis cells. Cortisol output by adrenal slices and homogenates per unit weight of the gland was higher in male than in female hamster. On the ground of these data, it seems conceivable that the observed sex-differences in the rate of cortisol output by hamster adrenal gland depend upon the higher number of the zona fasciculata cells and larger size of the zona reticularis cells in male than female gland.