From Big Medical Encyclopedia

HYPERCHOLESTEROLEMIA (grech, hyper-+ cholesterol + grech, haima blood) — increase in content of cholesterol in blood of St. 250 mg of %. Various methods of quantitative definition of cholesterol can give a little different indicators; e.g., the method of the Fisher which is often applied at mass inspections (see. Fishers method ) gives higher values. Also distinctions in standards of concentration of cholesterol in blood for persons of different gender and age are considered (see. Holesterin ).

At G. the volume of metabolic labile pool (stock) of the cholesterol (a pool And) including reserves of cholesterol in plasma, erythrocytes, bile, a liver, a wall of intestines, a spleen, kidneys increases: and lungs whereas the sizes of a pool of B (metabolic inert cholesterol which is a part of all proteinaceous and lipidic membranes) practically do not change (see. Holesterin ).

At healthy faces of G. arises at tranzitorny changes of functions of the neurohumoral device regulating activity of key enzymes at stages of absorption, synthesis and disintegration of cholesterol. In particular, G. is observed at excess consumption of cholesterol (alimentary G.), at an overstrain of century of N d, (emotional G.), at pregnancy and at first after the delivery.

Systematic surplus in food of animal fats (St. 40% of the general caloric content of a diet) and products rich with cholesterol can lead to firm alimentary G. though it does not reach a high level; the main part of cholesterol in this case is a part of beta lipoproteids of a blood plasma. Can lead to similar changes in blood even short-term strong nervous excitement. At pregnant women concentration of cholesterol in blood increases parallel to increase in duration of gestation. After delivery it is normalized, and at nursing mothers quicker as milk in the first weeks of feeding contains a lot of cholesterol.

In G.'s experiment it is possible to observe at traumatization of c. N of page, during the bandaging of ureters, at a resection of a thyroid gland or at medicamentous suppression of its function, during removal of a duodenum, adrenal glands, ovaries, and also at long administration of steroid hormones. The easiest in an experiment alimentary G. develops at the animals, in usual conditions who are not receiving cholesterol with food, napr at herbivorous.

In pathology of the person steady G. is connected usually with long disturbance cholesteric exchange (see), its regulation or mechanisms of transport of fats in a blood plasma. Distinguish primary (family), genetically caused G., and the secondary G. developing at different patol, processes and states. It is observed at the so-called cholesteric diathesis which is often proceeding with a xanthomatosis; at a diabetes mellitus, especially with a ketosis; at a hypothyroidism, obesity, gout, an idiopathic hypertensia (especially at its development in women along with a climax); at some diseases of a liver (in the most expressed degree — at biliary cirrhosis), at a cholelithiasis because of disturbances of exchange of cholesterol, at mechanical jaundice; quite often at hron, nephrites, amyloid and especially lipoid nephrosis; at some skin diseases (in particular, at psoriasis); at a number of diseases of c. N of page (abscess of a brain, an encephalomeningitis, diencephalic defeats, a brain stroke in an acute stage, maniac-depressive psychosis and some other), in the period of an anesthesia, at asphyxia; in an initial stage of a complete starvation, at hron, a hemodialysis. Often G. is caused by preferential increase in fraction of holesterinester (at a lipoid nephrosis, in an acute stage of a brain stroke, etc.). Increase in hl, obr is characteristic of G. at damages of a liver. free and decrease in esterified cholesterol.

G.'s genesis at various patol, states is not identical. At a diabetes mellitus with G.'s ketosis it is possible to explain with increase in synthesis of cholesterol from acetoacetic to - you. At a hypothyroidism the speed of removal of cholesterol since its turning into bile acids considerably decreases decreases,

G. at the beginning of a complete starvation connect with mobilization of lipids of fat depos under the influence of lipomobilizuyushchy hormones of a hypophysis, and at stressorny influences under the influence of increase in function of adrenal glands with emission in blood of large numbers not esterified fat to - t. Also other origins of G. are possible, apparently, (disturbance of exchange of carbohydrates, functions and flora of intestines, etc.). In many cases G.'s genesis is not known yet, napr, at cholesteric diathesis participation of hereditary and autoimmune factors is supposed.

It is considered that G. is one of important risk factors of development atherosclerosis (see), at the same time absolute concentration of cholesterol, how many a form of its stay in a blood plasma where cholesterol and its ethers can exist only in the form of proteinaceous and lipidic complexes matters not so much — lipoproteids (see), i.e. chylomicrons, lipoproteids of very low density (pre - beta lipoproteids), lipoproteids of the low density (beta lipoproteids) and lipoproteids of the high density (alpha lipoproteids). Always reflects increase in content in plasma of this or that fraction of lipoproteids. According to the WHO classification (1970) 5 types of giperlipoproteinemiya are allocated. The probability of development of atherosclerosis is high at G. caused by giperlipoproteinemiya of the IIA types (increase in plasma only of lipoproteids of low density), 116 (increase in lipoproteids of low and very low density), III (emergence of the floating p-lipoproteids), IV (increase in lipoproteids of very low density at datum level of chylomicrons and lipoproteids of low density) whereas G. at giperlipoproteinemiya of types I (chylomicronemia) and V (a chylomicronemia and increase in lipoproteids of very low density) is practically not followed by development of atherosclerosis. Giperlipoproteinemiya of type II (especially promoting: to development of atherosclerosis) can be primary, i.e. hereditary that proves existence of a hypercholesterolemia already in blood of an umbilical cord (at the same time possibly development of atherosclerosis at early children's age). It can develop and for the second time at a hypothyroidism, an amyloid and lipoid nephrosis, obturatsionny jaundice, at abuse of the food rich with cholesterol. At III and IV types are usually combined with development of atherosclerosis already at mature age. Therefore one fact of presence of G. is insufficient for assessment of the forecast of development of atherosclerosis and purpose of adequate therapy.

For G.'s reduction a number of means or reducing synthesis (Clofibratum and its analogs, tsetamifen, etc.), or slowing down absorption and increasing removal of food cholesterol (holestiramin, saponins, etc.), or stimulating exchange of cholesterol is used (drugs of a thyroid gland, high-unsaturated fat to - t, vitamins B 6 , C, etc.), or detaining emission in blood not esterified fat to - t (group of relatives to nicotinic to - those drugs).

Neurotropic means (a haloperidol, aminazine, Iprazidum, Niamidum, etc.) and heparinoids have some gipokholesterinemichesky effect (ateroid). Diets with the lowered caloric content, the reduced maintenance of animal fats, cholesterol, digestible carbohydrates are offered. At G.'s treatment it is necessary to consider type of a giperlipoproteinemiya; at II and III types restriction of food cholesterol and animal fats, increase in food of the fresh vegetable oils rich unsaturated fat to-tami, drugs like linaetholum in combination with vita of nomas B6, Clofibratum and its analogs, drugs of group nicotinic to - you in combination with tocopherol, hormones of a thyroid gland is necessary.

At the II type it is considered the most effective holestiramin or related to it drugs, and at the III type — Clofibratum; are shown are also oestrogenic. As type IV and especially III are combined with reduction of tolerance to glucose, at them decrease in food of digestible carbohydrates is recommended. At the IV type reception of Clofibratum, estrogen, nicotinic to - you is reasonable. In all cases normalization of a way of life, elimination of intoxications, increase in muscular activity at a balanced diet are necessary.

Bibliography: P. D. Znacheniye's horizons of a brain in cholesteric exchange (To a question of a role of a neuroglia in a pathogeny of cholesterinemias), M., 1940, bibliogr.; Klimov A. N. and Nikulche-v and N. G. Types of giperlipoproteinemiya, their communication with atherosclerosis and treatment, Cardiology, t. 12, No. 6, page 133, 1972, bibliogr.; Leytes S. M. and Lapteva H. H. Sketches on a pathophysiology of a metabolism and endocrine system, page 138, M., 1967, bibliogr.; Dressing gowns C. C. A cholesteric disease in its pathophysiological and clinical value, M., 1946, bibliogr.

See also bibliogr, to St. Atherosclerosis .

B. V. Ilyinsky, V. N. Uranov.