Endocrine system adrenal

Imura, H and Fukata, J., Endocrine-paracrine interaction in communication between the immune and endocrine systems. Activation of the hypothalamic-pituitary-adrenal axis in inflammation. Eur. J. Endocrinol. 130,32-37 (1994). 

All OCPs are polytropic, parenchymatous poisons, afflicting the central nervous system, liver, kidneys, the heart muscle, the stomach and intestines, and the endocrine system (mostly the adrenal glands, thyroid, and ovaries). Morphological changes in warm-blooded creatures poisoned by OCPs vary from insignificant disruptions in circulation and reversible dystrophy to focal necroses these effects depend on the organism, the dose of OCP, how long the OCP remains active, as well as on other factors [9, 39, 40, A47, A79]. 

An increase in plethora and focal dystrophic changes in the endocrine system matches clinical observations of changes in adrenal and thyroid function, as well as changes in local and general vascular dystonia, all detected in humans poisoned by OCP. Morphological changes in the brain s nerve cells conform to information on the disruption of reflex activity in the early stages of OCP exposure. 

Li+ has been reported to affect virtually every component of the endocrine system to some extent however any resulting clinical manifestations are very rare [169]. Although these influences do not appear to be related to its mechanism of action in manic-depression, some are involved in the side effects experienced by Li+-treated patients. Apart from elevated levels of thyroid stimulating hormone (TSH), Li+ does not appear to affect the basal levels of hormones significantly however some hormone responses are reported to be altered by Li+ treatment of bipolar patients [170]. Neuronal activity stimulates the adrenal medulla to release norepinephrine and epinephrine into the blood and, consequently, the plasma from people with mania and depression shows increased levels of both neurotransmitters [171]. 

Endocrine system Cushing s habitus, hirsutism, retardation of growth, suppression of hypothalamopituitary-adrenal axis. 

Use of Hormones in Nonendocrine Disease. There are many examples of how various hormones and hormone-related drugs can be used to treat conditions that are not directly related to the endocrine system. For instance, certain forms of cancer respond to treatment with glucocorticoids (see Chapter 36). Drugs that block the cardiac beta-1 receptors may help control angina and hypertension by preventing excessive stimulation from adrenal medulla hormones (epinephrine, norepinephrine see Chapters 21 and 22). 

Endocrine Effects. Little is known about the effects of aluminum on endocrine systems. The oral administration of sodium aluminum phosphate to male and female Beagle dogs for 6 months did not alter thyroid, adrenal, or pituitary gland weight or microanatomy (Katz et al. 1984 Pettersen et al. 1990). These organs were also normal in male and female Wistar rats fed a diet containing unspecified amounts of aluminum phosphide/ammonium carbamate for 24 months (Hackenberg 1972). 

The primary purpose of the endocrine system is to maintain homeostasis — that is, to maintain a relatively constant internal environment in the face of a constantly changing external environment. The endocrine system consists of hormones and the glands and tissues that produce the hormones. A hormone is a chemical substance released by certain cells to effect the function of other distant cells (endocrine function). Many compounds act as endocrine hormones as well as having paracrine and autocrine functions. Paracrine and autocrine describe actions on nearby cells and on other cells that produce the substance, respectively. There is considerable overlap between substances classified as hormones and other chemical messengers such as neurotransmitters and cytokines. Many substances function in more than one of these categories. For example, epinephrine and norepinephrine function as both neurotransmitters and adrenal medullary hormones. 

In the safety pharmacology protocol, the interaction of multiple endocrine systems in test animals is addressed. As discussed by Harvey (1996) and by Harvey and Everett (2003), effects on adrenocortical function are frequently found in toxicology studies, sometimes related to enzyme induction and effects on steroid biosynthesis (Loose et al. 1983, Nebert and Russell 2002, Weber et al. 1993). Test procedures in animals are required when there is a reason for concern. Frequently however the effects observed are due to stress rather than specific interaction with the target organ, and may involve effects on catecholamine release from the adrenal medulla (Tucker 1996). Recently, much new evidence has been accumulated from the testing of industrial chemicals with effects on adrenal steroid biosynthesis (Harvey and Johnson 2002). 

While the hydroxylases of the adrenals and other steroid producing tissues show some (variable) catalytic activity towards xenobiotics (e.g., benzo[a]pyrene) (17) this is probably fortuitous in nature and it seems that, in general, the enzymes are quite specific for their respective steroid substrates. Furthermore, the steroid hydroxylases of the endocrine system are not susceptible to the inductive effects of xenobiotics as are the cytochrome P-450-mediated oxidases of the liver and other tissues (17,18) indeed, this is not unexpected, since if they responded to the external environment in this way their critical homeostatic role would rapidly be compromized. 

Endocrine Effects. A single study was found that reported on possible effects of uranium on the endocrine system. In this study, no histopathology was seen in the endocrine organs (adrenal, pancreas) in rats given 0.2 mg U/m as uranium tetrachloride for 1 year (Stokinger et al. 1953). 

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