Glucocorticoid production (cortisol is the principal hormone) in the adrenal zona fasciculata and zona reticularis is controlled primarily by ACTH released from the anterior pituitary. Glucocorticoids inhibit the release of CRH and ACTH as part of a negative feedback mechanism. Glucocorticoids act on numerous tissues via the intracellular cytosol-nuclear receptor mechanism. They affect the sense of well-being, appetite, and mood. They promote hepatic gluconeogenesis and glycogen storage, promote protein catabolism, and decrease peripheral utilization of glucose in tissues. These concerted actions result in an increase in blood glucose concentration, which subsequently increases circulating insulin levels. Glucocorticoids are important for cardiovascular function. Glucosteroids have permissive effects on the vasopressor actions of norepinephrine and angiotensin II. These hormones increase synthesis of b-adrenergic receptors, reverse b-adrenergic dysfunction, and increase coupling between cell membrane b-adrenergic receptors and second-messenger systems.

Glucosteroids increase free water excretion by the kidneys and are also important for potassium homeostasis. They have mineralocorticoid-like renal effects, specifically in the absence of aldosterone. Glucocorticoids affect gastrointestinal motility. These hormones increase circulating neutrophils but impair their recruitment into an inflamed area and decrease the number of circulating lymphocytes, monocytes, eosinophils, and basophils. Effects on calcium homeostasis are inhibition of intestinal calcium absorption, increase of renal calcium excretion, and inhibition of osteoblast function. These various activities of glucocorticoids largely explain the clinical manifestations of glucocorticoid deficiency.

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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