In hormonal production

Although the kidneys are not considered endocrine glands per se, they are involved in hormone production. Erythropoietin is a peptide hormone that stimulates red blood cell production in bone marrow. Its primary source is the kidneys. Erythropoietin is secreted in response to renal hypoxia. Chronic renal disease may impair the secretion of erythropoietin, leading to development of anemia. The kidneys also produce enzymes. The enzyme renin is part of the renin-angiotensin-aldosterone system. As will be discussed, these substances play an important role in the regulation of plasma volume and therefore blood pressure. Other renal enzymes are needed for the conversion of vitamin D into its active form, 1,25-d i hyd ro xyv itamin D3, which is involved with calcium balance. 

Vitamins are small organic molecules which in small amounts are obligatory nutrients and used by the body as co-factors in a multitude of metabolic processes. They play a role in hormone production, are necessary for blood cell formation and for producing nervous-system constituents, and they are ingredients for the formation of genetic material. There are no chemical relationships between the various vitamins and mostly also their most physiological actions are not related. 

Positive feedback, in hormone production, 2-12 Post, H.W., 29-4 Postdeposition heat treatments, in dental implants, 45-27 Posttelanic potentiation, 3-4 Posture control mechanisms,... 

Sulfuric Acid 15 248 120 G — — plus supr from digestion of tuber barbasco. Process is for obtaining sterrad used in hormone production. -... 

Vitamin B6 plays a role in the metabolism of protein, carbohydrates and fats, the production of nemotransmitters and the formation of nicotinic acid. It is vital for maintaining a healthy nervous system, skin, muscles and blood. One of the central roles of this vitamin is in protein metabolism where it helps regulate the balance of amino acids in the body. It is also closely involved in hormone production. 

The major problem in such conversions is the degradation of the branched carbon side-chain on C-17 which is present in all abundant steroids and lacking in all steroid hormones. The most important starting material used in industry today is diosgenin from the Mexican dioscorea plant. It is degraded by the method of Marker to 16-dehydropregnenolone in 45% total yield. This compound is a key substance in the production of several hormones with anabolic, catabolic, and sexual effects. 

Amino acid-derived hormones include the catecholamines, epinephrine and norepinephrine (qv), and the thyroid hormones, thyroxine and triiodothyronine (see Thyroid AND ANTITHYROID PREPARATIONS). Catecholamines are synthesized from the amino acid tyrosine by a series of enzymatic reactions that include hydroxylations, decarboxylations, and methylations. Thyroid hormones also are derived from tyrosine iodination of the tyrosine residues on a large protein backbone results in the production of active hormone. 

Mammals, fungi, and higher plants produce a family of proteolytic enzymes known as aspartic proteases. These enzymes are active at acidic (or sometimes neutral) pH, and each possesses two aspartic acid residues at the active site. Aspartic proteases carry out a variety of functions (Table 16.3), including digestion pepsin and ehymosin), lysosomal protein degradation eathepsin D and E), and regulation of blood pressure renin is an aspartic protease involved in the production of an otensin, a hormone that stimulates smooth muscle contraction and reduces excretion of salts and fluid). The aspartic proteases display a variety of substrate specificities, but normally they are most active in the cleavage of peptide bonds between two hydrophobic amino acid residues. The preferred substrates of pepsin, for example, contain aromatic residues on both sides of the peptide bond to be cleaved. 

The metabolic rate is increased by several hormones including thyi oid hormone, adrenalin and male sex hormones. The increase in metabolic rate caused by male sex hormones explains why males have slightly higher average metabolic rates than females of the same size and age. Living in a cold climate increases the metabolic rate because the cold stimulates thyroid hormone production and this hormone increases heat output of the body, while living in a warm climate causes the metabolic rate to decrease. 

Hyperthyroidism (thyrotoxicosis), defined as excessive thyroid activity, causes a state of thyroid hormone excess (thyrotoxicosis) characterized by an increased metabolic rate, increase in body temperature, sweating, tachycardia, tremor, nervousness, increased appetite and loss of weight. Common causes of hyperthyroidism are toxic multinodular goiter, toxic adenoma or diffuse toxic goitre ( Graves disease). Antithyroid diugs (methimazol, carbimazole, propylthiouracil) block thyroid hormone production and are hence suitable for the treatment of hyperthyroidism. 

The serine proteases are the most extensively studied class of enzymes. These enzymes are characterized by the presence of a unique serine amino acid. Two major evolutionary families are presented in this class. The bacterial protease subtilisin and the trypsin family, which includes the enzymes trypsin, chymotrypsin, elastase as well as thrombin, plasmin, and others involved in a diverse range of cellular functions including digestion, blood clotting, hormone production, and complement activation. The trypsin family catalyzes the reaction ... 

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