The adrenals are paired glands that lie above the kidneys. They have an inner medulla and an outer cortex.
Glucocorticoids have anti-inflammatory activity.
When administered in supra-physiologic doses, they inhibit inflammatory and allergic reactions. Glucocorticoids have also effects on the nervous system, primarily of an excitatory nature, evidenced by the presence of hormone receptors on neurons and glia, induction of neurotransmitter enzymes, EEG changes and increased convulsibility, toxicity for specific neurons. Another important action of glucocorticoids is their negative feedback on hypothalamus and pituitary. Their secretion decreases markedly in old age. It increases sodium reabsorption from the renal tubular fluid, saliva and gastric juice.