Adrenocorticotropic hormone, metabolic

Anterior part produces its own hormones in response to hypothalamic releasing hormones, e.g., adrenocorticotropic hormone ACTH, luteinizing hormone LH, follicle-stimulating hormone FSH, prolactin, growth hormone, thyroid-stimulating hormone TSH Thyroid Regulation of metabolism, development, and maturation... 

Corticotropin (adrenocorticotropic hormone, ACTH) regulates the function of the adrenal cortex and has numerous other effects on metabolism. It contains 39 amino acids in the form of a random coil, owing to the presence of several proline residues that prevent helix formation. Species differences are seen in amino acids 25-39 the rest of the ACTH molecule is identical in all animals and humans. The first 24 amino acids are responsible for all of the biological action of ACTH synthetic human ACTHj 24 is known as cosyntropin. 

Other Hormones. Pituitary hormones regulate the function of many other endocrine glands, and hypophysectomy in male rats results in a decrease in the activity of xenobiotic metabolizing enzymes. Administration of adrenocorticotropic hormone (ACTH) also results in a decrease of those oxidative enzyme activities that are gender dependent. In contrast, ACTH treatment of female rats causes an increase in aminopyrine /V-dcmcthylasc but no change in other activities. 

Corticosteroids and adrenocorticotropic hormone have been widely used for the treatment of ulcerative cohtis and Crohn s disease, given parenterally, orally, or rectally. Corticosteroids are believed to modulate the immune system and inhibit production of cytokines and mediators. It is not clear whether the most important steroid effects are systemic or local (mucosal). Budesonide is a corticosteroid that is administered orally in a controlled-release formulation. The drug undergoes extensive first-pass metabolism, so systemic exposure is thought to be minimized. Immunosuppressive agents such as azathioprine, mercaptopurine (a metabolite of azathioprine), methotrexate, or cyclosporine are sometimes used for the treatment of IBD. ... 

Some of the rare causes of metabolic alkalosis due to potassium depletion are those found in subjects with either Cushing s syndrome, primary aldosteronism, or Bartter s syndrome. In Cushing s syndrome, the potassium ions and alkalosis are related to increased mineralocorticoid activity resulting from an increase in adrenocorticotropic hormone (ACTH), cortisol, deoxycorticosterone, and corticosterone. In primary aldosteronism, the effects of increased aldosterone are manifest on the distal tubule of the kidney. In Bartter s syndrome, the basic abnormality appears to be a defect in the reabsorption of chloride in the ascending limb of loop of Henle, leading to loss of potassium (12). 

The adrenal glands, which are divided into the medulla (core) and the cortex (outer layer), furnish catecholamines and steroids, respectively. The catecholamines are hormonally active, and consist of norepinephrine and epinephrine. Steroids variously affect carbohydrate, protein, and lipid metabolism, regulate the sall/water losses of the kidneys, and affect sexual development and function. Androgens and estrogens fall in the last-mentioned category. Another adrenal hormone of note is ACTH, or adrenocorticotropic hormone. Cortisol is an adrenal product, which can be converted to cortisone. 

Melatonin occurs in the pineal gland and is the biochemical clock in the brain (Bartsch 1994). Various forms of mental illness may respond to melatonin therapy Maurizi 1984) (Brown 1995). Melatonin blocks the actions of melanocyte-stimulating and adrenocorticotropic hormones (Axelrod). There are several synthetic methods used to produce melatonin (Szmuszkovicz 1959), Metabolism of melatonin see (Kopin 1961) (Kveder 1961). 

The actions of hormones are very diverse. Some, e.g. glucagon, have specific and clearly defined effects on the metabolism of particular tissues. Others such as growth hormone and the sex hormones have more general effects on growth and development while the tropic hormones stimulate their target tissues to secrete further hormones. For example the adrenocorticotropic hormone (ACTH), which is produced in the anterior pituitary, promotes the synthesis and release of glucocorticoids by the adrenal cortex. A list of some of the hormones and their effects on metabolism is given in Table 24.1. 

In other situations, stress factors such as emotional disturbances, fasting, starvation, or diabetes, are signals to the pituitary gland to release adrenocorticotropic hormone (ACTH), which acts both alone on tissues and stimulates secretion of other stress hormones by the adrenal glands. The net effects of these stress-responsive hormones are the tearing down (catabolism) of fat, muscle, and/or bone tissues, so as to provide essential nutrients for metabolism. 

Leboeuf, B., and G. F. Cahill jr. Studies on rat adipose tissue in vitro. VIII. Effect of preparations of pituitary adrenocorticotropic and growth hormone on glucose metabolism. J. biol. Chem. 236, 41 (1961). 

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