Adrenal gland,

The adrenal glands play an important role in pubertal development. Termed adrenarche, the maturation of a prominent zona reticularis, the innermost layer of the cortex, begins around age six to eight in girls, resulting in increased secretion of the adrenal androgens, dehydroepiandrosterone (DHEA) and DHEA sulfate (Beckman Feuston, 2003). The rise in these hormones leads to the development of pubic and axillary hair. Recent evidence suggests 

There are two adrenal glands, one located on top of each kidney. These glands are composed of two distinct functional regions  

Adrenal medulla. Derived from neural crest tissue, the adrenal medulla forms the inner portion of the adrenal gland. It is the site of production of the catecholamines, epinephrine and norepinephrine, which serve as a circulating counterpart to the sympathetic neurotransmitter, norepinephrine, released directly from sympathetic neurons to the tissues. As such, the adrenal medulla and its hormonal products play an important role in the activity of the sympathetic nervous system. This is fully discussed in Chapter 9, which deals with the autonomic nervous system. 

Adrenal cortex. The adrenal cortex forms the outer portion of the adrenal gland and accounts for 80 to 90% of the weight of the gland. It is the site of synthesis of many types of steroid hormones such as  

Mineralocorticoids. The primary mineralocorticoid is aldosterone. The actions of this hormone include  

Aldosterone acts on the distal tubule of the nephron to increase sodium reabsorption. The mechanism of action involves an increase in the number of sodium-permeable channels on the luminal surface of the distal tubule and an increase in the activity of the Na+-K+ ATPase pump on the basilar surface of the tubule. Sodium diffuses down its concentration gradient out of the lumen and into the tubular cells. The pump then actively removes the sodium from cells of the distal tubule and into the extracellular fluid so that it may diffuse into the surrounding capillaries and return to the circulation. Due to its osmotic effects, the retention of sodium is accompanied by the retention of water. In other words, wherever sodium goes, water follows. As a result, aldosterone is very important in regulation of blood volume and blood pressure. The retention of sodium and water expands the blood volume and, consequently, increases mean arterial pressure. 

Calcitonin is used in the treatment of Paget s disease and osteoporosis (see Chapter 7). 

The adrenal glands are situated one above each kidney. 

They have two separate parts an inner medulla derived from nerve tissue and an outer cortex, which is typically endocrine in structure. 

The adrenal medulla secretes adrenaline (80%) and noradrenaline (20%). They have similar physiological effects, which augment activation of the sympathetic nervous system. 

The adrenal cortex is made up of three distinct layers, each of which secretes a different type of steroid hormone. 

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Cortisone is a hormone produced by the cortex of the adrenal glands. As with other adrenal corticoid steroids, administration of cortisone leads to an increased deposition of liver glycogen. Tt can remove features of rheumatoid arthritis, but does not check the underlying disease it is used in various diseases of the eye, and is an antiallergic and anlifibroplastic agent. 

Also called adrena/rne a hormone secreted by the adrenal gland that prepares the organism for flight or fight )... 

The outer layer or cortex of the adrenal gland is the source of a large group of sub stances known as corticosteroids Like the bile acids they are derived from cholesterol by oxidation with cleavage of a portion of the alkyl substituent on the D ring Cortisol IS the most abundant of the corticosteroids but cortisone is probably the best known Cortisone is commonly prescribed as an antiinflammatory drug especially m the treat ment of rheumatoid arthritis... 

Three tachykinin GPCRs, NK, NK, and NK, have been identified and cloned. AH are coupled to phosphatidjhnositol hydrolysis. The NK receptor is selective for substance P (SP) and is relatively abundant in the brain, spinal cord, and peripheral tissues. The NK receptor is selective for NKA and is present in the gastrointestinal tract, urinary bladder, and adrenal gland but is low or absent in the CNS. The NIC receptor is selective for NKB and is present in low amounts in the gastrointestinal tract and urinary bladder, but is abundant in some areas of the CNS, ie, the spinal dorsal bom, soUtary nucleus, and laminae IV and V of the cortex with moderate amounts in the interpeduncular nucleus. Mismatches in the distribution of the tachykinins and tachykinin receptors suggest the possibility of additional tachykinin receptor subtypes. 

The uses of corticosteroid antiinflammatory dmgs in veterinary medicine are many and varied. In the intact animal, the glucocorticoids and mineralcorticoids are produced in the adrenal glands. Exogenous compounds are, therefore, used for their glucogenic physiologic effect in cases where the... 

The adrenal glands and pituitary glands have the highest tissue concentration of ascorbic acid. The brain, Hver, and spleen, however, represent the largest contribution to the body pool. Plasma and leukocyte ascorbic acid levels decrease with increasing age (152). Elderly people require higher ascorbic acid intakes than children to reach the same plasma and tissue concentration (153). 

Relatively Httie is known about the bioavailabiUty of pantothenic acid in human beings, and only approximately 50% of pantothenic acid present in the diet is actually absorbed (10). Liver, adrenal glands, kidneys, brain, and testes contain high concentrations of pantothenic acid. In healthy adults, the total amount of pantothenic acid present in whole blood is estimated to be 1 mg/L. A significant (2—7 mg/d) difference is observed among different age-group individuals with respect to pantothenic acid intake and urinary excretion, indicating differences in the rate of metaboHsm of pantothenic acid. 

The original commercial source of E was extraction from bovine adrenal glands (5). This was replaced by a synthetic route for E and NE (Eig. 1) similar to the original pubHshed route of synthesis (6). Eriedel-Crafts acylation of catechol [120-80-9] with chloroacetyl chloride yields chloroacetocatechol [99-40-1]. Displacement of the chlorine by methylamine yields the methylamine derivative, adrenalone [99-45-6] which on catalytic reduction yields (+)-epinephrine [329-65-7]. Substitution of ammonia for methylamine in the sequence yields the amino derivative noradrenalone [499-61-6] which on reduction yields (+)-norepinephrine [138-65-8]. The racemic compounds were resolved with (+)-tartaric acid to give the physiologically active (—)-enantiomers. The commercial synthesis of E and related compounds has been reviewed (27). The synthetic route for L-3,4-dihydroxyphenylalanine [59-92-7] (l-DOPA) has been described (28). 

D 0.07 0.07 Kidney, liver, or adrenal gland nroblems Runoff from herbicide used on row crops... 

Trichlorobenzene 0.07 0.07 Changes in adrenal glands Discharge from textile finishing factories... 

Also called adrenaline a hormone secreted by the adrenal gland that prepares the organism for "flight or fight.") (A hormone synthesized in the pineal gland. Certain mental disorders are believed to be related to serotonin levels in the brain.)... 

Testosterone is also produced primarily in the ovaries (and in much smaller amounts in the adrenal glands) of females as a precursor for the estrogens. /3-Estradiol is the most important estrogen (Eigure 25.43). 

It was known as early as 1927 that the adrenal glands of mammalian species secrete a series of substances essential to the survival of the individual. The hormonal nature of these secretions was suggested by the observation that extracts of the adrenal gland and more specifically of the outer portion of that organ (cortex) would ensure survival of animals whose adrenals had been excised. By 1943 no fewer than 28 steroids had been isolated from adrenal cortical extracts. These compounds were found to be involved in the regulation of such diverse and basic processes as electrolyte balance, carbohydrate metabolism, and resistance to trauma, to name only a few. 

Epinephrine may be made by isolation from animal adrenal glands or may be synthesized as described by Payne in Ind. Chemist, 37, 523 (1961). 

C27H45OH, crystallising in the form of acicular crystals and found in all animal fats and oils, in bile, blood, brain tissue, milk, yolk of egg, the medullated sheaths of nerve fibres, the liver, kidneys and adrenal glands. 

Hydrocortisone, a naturally occurring hormone produced in the adrenal glands, is often used to treat inflammation, severe allergies, and numerous other conditions. Is the indicated -OH group in the molecule axial or equatorial ... 

Adrenocortical hormone (Section 27.6) A steroid hormone secreted by the adrenal glands. There are two types of adrenocortical hormones mineralocorticoids and glucocorticoids. 

An endocrine disorder first described by the British Physician Thomas Addison in the mid 1800 s. The adrenal glands fail to produce sufficient amounts of glucocorticoid hormones (cortisol) and sometime mineralocorticoid (aldosterone). If left untreated it is life-threatening, the patient will show muscle weakness, hyperpigmentation and even depression. Typical treatment is hydrocortisone replacement therapy. 

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