In the cow and sheep, the zona fasciculata is further divided into inner and outer layers. The middle zone, the zona fasciculata, is relatively wide, and its cells are organized in columns. The outer zone, the zona glomerulosa, is relatively narrow, and its cells are organized in a whorl-type arrangement. The adrenal cortex is organized into three zones in mammals (see Fig. Greco, in Cunningham's Textbook of Veterinary Physiology (Sixth Edition), 2020 The Adrenal Cortex Has Three Zones: the Zona Glomerulosa, Which Secretes Mineralocorticoids, and the Zona Fasciculata and the Zona Reticularis, Which Secrete Glucocorticoids and Sex Steroids This remains the least understood aspect of the function of the adrenal cortex.īrian K. In late childhood, there is a significant rise in adrenal sex steroid production, termed the adrenarche, leading to further complex interactions with the hypothalamus–pituitary axis and the gonads in preparation for puberty and the transition to sexual maturity ( 6). The major sex steroids secreted by the adrenal cortex are dehydroepiandrosterone (DHEA) and its sulfate androgenic steroids and estrogens are normally very minor products. Several studies have defined important mediating roles for GCs in the functioning of the immune response ( 2– 5). It is indispensable for proper carbohydrate metabolism and in ensuring systemic capacity to withstand events of stress such as infection and trauma. The primary site of action of aldosterone is at the renal distal convoluted tubules and the cortical collecting ducts, where it promotes reabsorption of the crucial 2% of sodium to be regained from the renal filtrate.Ĭortisol, the principal GC in humans and most mammalian primates ( 1) is quantitatively the main secretory product of the adrenal cortex.

It is the most potent steroid affecting active transport of sodium ions across membranes and thus in maintaining electrolyte balance. In: Genetic and Molecular Biological Aspects of Endocrine Disease Balliere Tindall: London, 1995, pp: 526.)Īldosterone is the end product of the MC pathway.

Adrenal gland secretes