ADRENALEMIA

From Big Medical Encyclopedia

ADRENALEMIA (adrenaline + Greek haima — blood) — the content of adrenaline in blood.

Adrenaline (see) in blood is in a stand-at-ease, in the form of compounds of sulfuric and glucuronic acids, in connection with proteins and uniform elements (thrombocytes, erythrocytes).

Size A. depends on a ratio of speed of secretion of adrenaline chromaffin cells and its eliminations from blood (adsorption by fabrics, exchange transformations, removal with urine, then, etc.), and also on the volume of the circulating blood.

Changes of ratios of the specified factors can lead to a hyperadrenalemia or a hypoadrenalemia. Changes of content of adrenaline in blood can have physiological character, reflecting participation of marrow of adrenal glands (see) in regulation of functions (at change of a sugar content in blood, during the cooling, physical tension, emotional reactions, etc.). Degree and duration hyper - or hypoadrenalemias at the same time depend at most and time of action of an irritant. Patholologically the expressed hyperadrenalemia can accompany a pheochromocytoma, a tumor or an inflammation of some sites of a brain, preferential diencephalic area (influence of these sites of a brain on secretion of adrenaline), insufficiency of bark of adrenal glands, insufficiency of kidneys (reduction of excretion of adrenaline). The Tranzitorny hyperadrenalemia is noted during the smoking (excitement of adrenalinotsit by nicotine), introduction of a histamine, tiramii, at a stress (emotional overexcitation, an injury, hemodynamic frustration, a pain syndrome).

At irritation of various receptor zones the ratio of adrenaline and noradrenaline in blood is not identical. Degree of a hyperadrenalemia at surgical intervention changes depending on duration and injury of operation, from a look and depth of an anesthesia, from conditions of carrying out operation.

Between the content of adrenaline in blood and its physiological effect there is no direct dependence, however a hyperadrenalemia, especially long, negatively influences metabolism, worsening utilization of oxygen cells, causing their dystrophy, exhaustion of fatty put, etc.

The hypoadrenalemia meets less often and has smaller value for pathology owing to a replaceable role of a sympathetic mediator. It can be result of an underdevelopment of marrow of adrenal glands (it leads to a hypoglycemia at early children's age), the investigation of a total adrenalectomy, functional exhaustion of marrow of adrenal glands at long action of exciting factors, etc.

Quantitative assessment And. it is possible by means of chemical (fluorimetrichesky), biological and isotope methods. At use of fluorimetrichesky methods of a research concentration of adrenaline in plasma, according to various authors, at adult healthy people makes from 0 to 0,62 mkg/l, at children — to 2 mkg/l, at various animals — from 0 to 5 mkg/l. There is an opinion that adrenaline in blood of the person normal is practically not defined, however it is based preferential on results of a research of plasma where concentration of adrenaline is really close to limit of sensibility of fluorimetrichesky methods. In clinical practice determination of sizes A. in most cases has no essential advantages before definition of catecholamines (see) in urine. Considering fluctuations of sizes A., the most chain data can be received continuous control of the content of adrenaline in blood — in an experiment, using Vane's method (J. R. Vane, 1966), and also comparing the content of adrenaline in blood and urine (assessment of renal clearance of adrenaline) or comparing concentration of adrenaline and noradrenaline in the blood taken by means of a catheter at the different levels of the lower and upper venas cava at topical diagnosis of extraadrenal pheochromocytomas.

Bibliography: Matlin E. Sh. and Menshikov V. In - Clinical biochemistry of catecholamines, M., 1967; Menshikov V. V. Methods of clinical biochemistry of hormones and mediators, M., 1969; Martin L. To. Harrison C. An automated method for determination of noradrenaline and adrenaline in tissues and bioiogical fluids, Analyt. Biochem., v. 23, p. 529, 1968, bibliogr.; Staszewska-Bar-czak J. Ceremuzynski L. The continuous estimation of catecholamine release in the early stages of myocardial infarction in the dog, Clin. Sci., v. 34, p. 513, 1968; Vane J. R. The estimation of catecholamines by biological assay, Pharmacol. Rev., v. 18, p. 317, 1966; Wcil-Mal-berbc H. a. In i g e i about w L. B. The flu-orometric estimation of epinephrine and norepinephrine, Analyt. Biochem., v. 22, p. 321, 1968.

V. V. Menshikov.

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