Steroid hormones are produced and released in response to hormonal signals. Different regions of the adrenal cortex synthesize and secrete corticosteroids and androgens, which are then released into the bloodstream based on different signals. The adrenal medulla, on the other hand, produces catecholamines. 

The production of cortisol, a glucocorticoid, takes place in the middle layer of the adrenal cortex called the zona fasciculata. This process is controlled by the hypothalamus, which is attached to the pituitary gland. When the body experiences severe stress, the hypothalamus produces corticotropin-releasing hormone (CRH). CRH travels through capillaries to the anterior lobe of the pituitary, stimulating the production and secretion of adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal cortex to synthesize and secrete cortisol. Cortisol helps the body respond to stress by affecting intermediary metabolism and reducing the inflammatory and immune responses. As cortisol levels increase, the release of CRH and ACTH is inhibited. 

The production of aldosterone, a mineralocorticoid, occurs in the outer layer of the adrenal cortex known as the zona glomerulosa. It is induced by a decrease in the plasma sodium/potassium ratio and by angiotensin II (Ang-II), a hormone. Ang-II is produced from angiotensin I (Ang-I) by angiotensin-converting enzyme (ACE), which is mainly found in the lungs but also distributed throughout the body. Ang-II binds to cell surface receptors and exerts its effects through the phosphatidylinositol 4,5-bisphosphate pathway. Aldosterone primarily affects the kidney tubules, where it promotes the uptake of sodium and water and the excretion of potassium. This leads to an increase in blood pressure. 

Both the inner (zona reticularis) and middle layers of the adrenal cortex produce androgens, such as dehydroepiandrosterone and androstenedione. Although adrenal androgens themselves are weak, they can be converted into stronger androgens, like testosterone, in the testes. In premenopausal women, they can also be converted into estrogens in the ovaries. Postmenopausal women produce estrogen at extragonadal sites like the breast. Aromatase inhibitors are used to treat estrogen-responsive breast cancer in these women. 

In summary, the adrenal cortex plays a crucial role in the production and secretion of corticosteroids, mineralocorticoids, and androgens, which have various effects on the body's response to stress, electrolyte balance, and sexual development.
Steroid hormones are synthesized and secreted in response to hormonal signals. The corticosteroids and androgens are made in different regions of the adrenal cortex and are secreted into blood in response to different signals. [Note: The adrenal medulla makes catecholamines (see p. 285).] 1. Cortisol: Its production in the middle layer (zona fasciculata) of the adrenal cortex is controlled by the hypothalamus, to which the pituitary gland is attached (Fig. 18.26). In response to severe stress (for example, infection), corticotropin-releasing hormone (CRH), produced by the hypothalamus, travels through capillaries to the anterior lobe of the pituitary, where it induces the production and secretion of adrenocorticotropic hormone (ACTH), a peptide. ACTH stimulates the adrenal cortex to synthesize and secrete the glucocorticoid cortisol, the stress hormone. [Note: ACTH binds to a membrane G protein–coupled receptor, resulting in cyclic AMP (cAMP) production and activation of protein kinase A ([PKA] see p. 94). PKA phosphorylates and activates both the esterase that converts cholesteryl ester to free cholesterol and StAR protein.] Cortisol allows the body to respond to stress through its effects on intermediary metabolism (for example, increased gluconeogenesis) and the inflammatory and immune responses (which are decreased). As cortisol levels rise, the release of CRH and ACTH is inhibited. [Note: The reduction of cortisol in CAH results in a rise in ACTH that causes adrenal hyperplasia.] 2. Aldosterone: Its production in the outer layer (zona glomerulosa) of the adrenal cortex is induced by a decrease in the plasma Na+/potassium (K+) ratio and by the hormone angiotensin II (Ang-II). Ang-II (an octapeptide) is produced from angiotensin I ([Ang-I] a decapeptide) by angiotensinconverting enzyme (ACE), an enzyme found predominantly in the lungs but also distributed widely in the body. [Note: Ang-I is produced in the blood by cleavage of an inactive precursor, angiotensinogen, secreted by the liver. Cleavage is catalyzed by renin, made and secreted by the kidneys.] Ang-II binds to cell surface receptors. However, in contrast to ACTH, its effects are mediated through the phosphatidylinositol 4,5bisphosphate pathway (see p. 205) and not by cAMP. Aldosterone’s primary effect is on the kidney tubules, where it stimulates Na+ and water uptake and K+ excretion (Fig. 18.27). [Note: An effect of aldosterone is an increase in blood pressure. Competitive inhibitors of ACE are used to treat renin-dependent hypertension.] 3. Androgens: Both the inner (zona reticularis) and middle layers of the adrenal cortex produce androgens, primarily dehydroepiandrosterone and androstenedione. Although adrenal androgens themselves are weak, they are converted by aromatase (CYP19) to testosterone, a stronger androgen, in the testes and to estrogens in the ovaries (primarily) of premenopausal women. [Note: Postmenopausal women produce estrogen at extragonadal sites such as the breast. Aromatase inhibitors are used in the treatment of estrogen-responsive breast cancer in these women.]
C. Gonadal steroid hormones