Hormone mechanisms

ALLOSTERIC HORMONAL MECHANISMS ARE IMPORTANT IN THE METABOLIC CONTROL OF ENZYME-CATALYZED REACTIONS... 

Metabolic Hormonal Mechanisms Regulate the Concentration of the Blood Glucose... 

The hormonal mechanisms of action to regulate glycogenesis and glycogenol-ysis involve reversible phosphorylation of the critical enzymes glycogen synthase and phosphorylase, respectively (Figure 6—6). 

Thyroid hormone mechanisms of action can be classified into two types (1) genomic or nuclear and (2) nongenomic, including effects at the plasma membrane and mitochondria. Genomic effects involve modification of gene transcription, are mediated only by Tj, and require at least several hours to detect. Nongenomic actions are generally rapid in onset and occur in response to T4 and some T4 metabolites (e.g., rT3,T3, and Tj). 

Zhao, E, E. Ghezzo-Schoneich, G.I. Aced, J. Hong, T. MUby, and C. Schoneich, Metal-catalyzed oxidation of histidine in human growth hormone. Mechanism, isotope effects, and inhibition by a mild denaturing alcohol. J Biol Chem, 1997.272(14) 9019-29. 

The indirect effects of nitroglycerin consist of those compensatory responses evoked by baroreceptors and hormonal mechanisms responding to decreased arterial pressure (see Figure 6-7) this often results in tachycardia and increased cardiac contractility. Retention of salt and water may also be significant, especially with intermediate- and long-acting nitrates. These compensatory responses contribute to the development of tolerance. 

Chapters 20 through 22 describe the major anabolic pathways by which cells use the energy in ATP to produce carbohydrates, lipids, amino acids, and nucleotides from simpler precursors. In Chapter 23 we step back from our detailed look at the metabolic pathways—as they occur in all organisms, from Escherichia coli to humans—and consider how they are regulated and integrated in mammals by hormonal mechanisms. 

Osborne, D.J. (1968). Hormonal mechanisms regulating senescence and abscission. Biochemistry and Physiology of Plant Growth Substances (Wightman, F. Setterfield, G Eds.), pp. 815-840. The Runge Press, Ottawa. 

The exact mechanism of action is not known, but various possibilities have been suggested. Mammary tumorigenesis is clearly influenced by hormones, and high-fat diets may alter the hormonal pattern in ways that favor tumor growth (16,17). It seems less likely that a hormonal mechanism would be involved in effects of dietary fat... 

The negative implications for pest control by precocenes themselves are clear, but it remains to be seen whether the expansion of their spectrum of activity is limited merely by the chemical structural features of precocenes or, more problematically, by the hormonal mechanisms which control insect development. In either case the JH antagonist approach to the control of larval insect pests presents a major challenge to chemical and physiological research. 

Beresford N, Routledge EJ, Harris CA, Sumpter JP (2000) Issues arising when interpreting results from an in vitro assay for estrogenic activity. Toxicol Appl Pharmacol 162 22-33 Creasy DM (1999) Hormonal Mechanisms in Male Reproductive Tract Toxicity. In Harvey PW, Rush KC, Cockbum A (eds) Endocrine and Hormonal Toxicology. John Wiley Sons, England, pp 355 106... 

In summary, carcinogenicity can be induced by genotoxic mechanisms which alter the genetic code or by epi-genetic mechanisms which act e.g. via disturbance of hormonal mechanisms. 

Gastric secretion and motility are controlled by both nervous and hormonal mechanisms. The vagus initiates the cephalic phase of secretion in response to the sight or smell of food, before food is eaten. The gastric phase occurs when food enters the stomach and is controlled both by intrinsic nerve reflexes in the stomach wall and released gastrin. The third, or intestinal, phase of secretion is coordinated by nervous and hormonal mechanisms to limit the release of the chyme from the stomach into the duodenum and reduces further acid secretion. 

Badawy AA and Evans M (1975) Regulation of rat liver tryptophan pyrrolase by its cofactor haem experiments with haematin and 5-aminolaevulinate and comparison with the substrate and hormonal mechanisms. Biochemical Journal 150, 511-20. 

Ivy AC, Oldberg E. Hormone mechanism for gall-bladder contraction and evacuation. Am. J. Physiol. 1928 86 599-613. 

G68. Gregory, R. A., Gastric secretion A review of its chief nervous and hormonal mechanisms. In Surgical Physiology of the Gastro-Intestinal Tract (A. N. Smith, ed.), pp. 57-70. Roy. Coll. Surg., Edinburgh, 1962. 

In contrast to the endocrine system that achieves long-term control via chemical (hormonal) mechanisms, the nervous system relies on more rapid mechanisms of chemical and electrical transmission to propagate signals and commands. The rapid conduction of impulses is essential in allowing the nervous system to mediate shortterm and near immediate communication and control between various body systems. 

Animal Production. Production of livestock that are leaner, faster growing, more disease free and more genetically sound than current breeds at less cost to the producer meets production efficiency goals to be attained. The animal scientists are researching metabolic and hormonal mechanisms to manipulate the rates nutrients are distributed into muscle, fat, and bone. 

Steroid and Thyroid Hormone Mechanisms The Insulin Receptor... 

In Section 16.5, each type of hormone mechanism is briefly described. This is followed by a discussion of the insulin receptor, a critically important cellular component. 

A Singular Hormonal Mechanism. I suppose one can debate whether or not angiotensin should be called a hormone. It is an internal secretion from the kidneys and functions, at least in part, as a regulator not only of smooth muscle but of aldosterone secretion. If the catecholamines are considered hormones, why not angiotensin ... 

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