From Big Medical Encyclopedia

SALIVA (saliva) — the secret of sialadens which is allocated in an oral cavity and participating in digestion.

In an oral cavity the secret of parotid, submaxillary, hypoglossal glands, small sialadens of an oral cavity is allocated (see. Sialadens ), forming the mixed S., or so-called oral liquid. The mixed S. differs from the secret which is allocated directly from channels of glands, presence of constant microflora, bacteria, fungi, spirochetes, etc. are a part a cut (see. Roth, oral cavity, microflora of an oral cavity ), and also products of their metabolism, desquamated epithelial cells, salivary little bodies representing the leukocytes migrating in an oral cavity of hl. obr. through a mucous membrane of a gingiva. Besides, at the mixed S. there can be a phlegm and allocations from a nasal cavity, erythrocytes, etc.

At the adult normal about 2,0 l of saliva are allocated per day. Speed of secretion of S. is uneven: at wakefulness out of meal it makes apprx. 0,5 ml/min., is minimum during sleep — - less than 0,05 ml/min., is maximum at stimulation of salivation — to 2,3 ml/min.

Moistening and softening firm food, S. provides formation of a food lump and facilitates a proglatyvaniye of food. After S.'s treatment food already in an oral cavity is exposed to initial chemical processing, in process a cut carbohydrates are partially hydrolyzed by alpha amylase (see. Amylases ) to dextrins and a maltose. Dissolution in S. of the chemical substances which are a part of food promotes perception of taste the flavoring analyzer. The village has protective function, clearing teeth (see) and a mucous membrane of a mouth (see Roth, an oral cavity) from bacteria and products of their metabolism, the remains of food, a detritis. A protective role is played also by immunoglobulins and lysozyme (see), contained in Page. As a result of secretory activity of big and small sialadens the mucous membrane of a mouth is moistened that is a necessary condition for implementation of bilateral transport of chemical substances between a mucous membrane of a mouth and S. Gidroksiapatit, being the main mineral component of enamel of tooth and necessary for its remineralization, it can be dissolved very poorly in S.

Smeshannaya S. represents a viscous liquid with specific weight from 1,001 to 1,017. S.'s viscosity is caused by presence glycoproteins (see). Nek-raya S.'s turbidity is caused by existence of cellular elements. Fluctuations of pH of saliva depend from a gigabyte. conditions of an oral cavity, character of food. With a low speed of secretion of pH of saliva moves in the acid party, at stimulation of salivation — in alkaline.

The page consists of water (about 99,5%), and also organic and mineral substances dissolved in it. The main organic matters C. are proteins, including synthesized in sialadens and out of them. In sialadens a part of enzymes, glycoproteins are synthesized, mucins (see) and immunoglobulins of a class of A. S by the help of immune and immunochemical methods it is shown that a part of proteins C. is proteins of a serumal origin. It enzymes (see), albumine (see), beta lipoproteids (see. Lipoproteids ), glycoproteins (see), immunoglobulins of classes G and M (see. Immunoglobulins ), transferrin, ceruloplasmin (see. Blood ).

Species-specific antibodies (see) and antigens (see), S. which are a part, correspond to a blood group (see. Blood groups ). Concentration of group antigens A and B in saliva is higher, than in blood serum and other liquids of an organism. Persons with a blood group 0 in S. have antigen N, specific to them. However almost 20% of people, so-called nesekre-tor, unlike secretaries, have not enough group antigens in S. or absolutely not. In S. it is possible to select donors with a universal blood group for the content of agglutinins. Способ^ a nost to cosecrete group-specific substances in S. it is descended as a dominant character and clearly it is expressed already at newborns.

I. Ito with sotr. (1960) opened in S. the person of squirrels salivaparotin with a molecular weight (weighing) 15 900, inducing adjournment of phosphorus-calcium connections in teeth. Phosphoprotein, kaltsiysvyazyvayushchy protein, protein with high affinity to a hydroxyapatite are also found in S. promoting education dental calculus (see) and dental plaque.

In the mixed S. is twice lower, than in blood, the level of residual nitrogen (108 — 206 mg/l), to-ry it is generally presented by an urea nitrogen, nitrogen uric to - you and free amino acids (see. residual nitrogen ). Concentration of cyclic AMF in the mixed S. of the person fluctuates from 5 to 50 nmol/l.

Of the person contains in the mixed S. apprx. 30 mg/l of free monosaccharides (including apprx. 10 mg/l of glucose), 18 — 40 mg/l of a lactate, 2 — 4 mg/l of pyruvate, 2 — 20 mg/l of citrate.

At the mixed S. in small amounts there are a cholesterol, its ethers, free fat to - you, glycerophospholipids, hormones (cortisol, a cortisone, estrogen, progesterone, testosterone), vitamins (thiamin, Riboflavinum, a pyridoxine, biotin, ascorbic, nicotinic, pantothenic and folic acids).

The mixed S. is much richer with enzymes, than a secret of separate glands that is caused by existence of cellular elements. In the mixed S. of the person the enzymes participating in processes of glycolysis (see) including multiple forms are found lactate dehydrogenases (see), in a cycle of tricarboxylic acids (see. Tricarboxylic acids cycle ), including. malate dehydrogenase (see), in phosphorylation (see), and also amylases (see), lipases (see), aminotransferases (see), peptide-hydrolase (see), ribonucleases (see) etc.

Various mineral substances and connections are S.'s part: anions of chlorides, bromides, fluorides, iodides, phosphates, bicarbonates, rhodanates, etc. Cations are presented by ions of sodium, potassium, calcium, magnesium, iron, copper, strontium, etc. More than a half of calcium in S. is ionized, other part is in a complex connected to phosphates or connected with proteins. Buffer properties of saliva are defined by bicarbonates, proteins and phosphates.

In a wedge, practice quantitative and qualitative methods of a research C. are widely used, to-rye apply for diagnosis, studying of dynamics and forecasting of diseases of sialadens, teeth, a mucous membrane of an oral cavity.

Treat methods of a research C. laboratory, including biochemical and tsitol. methods, and also radiological and tool methods of a research. For the purpose of studying of secretory function of sialadens determine total quantity of S. and speed its secretions (sialometriya) by capsules Lesh by l and — Yushchenko — Krasnogorsk (see. Salivation ) and radioiodine. Tsitol. the research C. helps to reveal morfol. changes of fabrics and bodies of an oral cavity. E.g., at an inflammation of a mucous membrane of a mouth or sialadens in S. the quantity of leukocytes and slushchivshikhsya epithelial cells sharply increases. Bakteriol. the research C. matters at establishment of an etiology of diseases of bodies of an oral cavity (see. Stomatitis ). Have important diagnostic value biochemical methods of a research (see) saliva.

At a research of mechanisms of formation of chemical structure S.Yu. A. Petroviç and R. P. Roadside (1977) revealed the selectivity of secretion of each ion and organic component C. caused by features of inclusion of each component C. in metabolism of a sialaden, allocation by its acinar cells (glandulotsita), allocations and reabsorptions cells of output channels; a number of bio-elements is transported in S. through a mucous membrane of a mouth. The alien substances getting to an organism at use of pharmaceuticals or poisoning, napr barbiturates, lithium, arsenic, bismuth, mercury, pass into saliva by means of the same mechanisms, as bio-elements.

The chemical structure of a secret of various sialadens is not identical. The chemical players of S. are changed depending on character of the activator of secretion, from the speed of secretion. E.g., at consumption of cookies, candies the level of glucose and a lactate temporarily increases in the mixed S. At stimulation of salivation in S. concentration of sodium and bicarbonates sharply increases, does not change or a little the level of potassium and iodine decreases. In S. of smokers much more rhodanates (60 — 120 mg/l), than at non-smoking (10 — 30 mg/l). Chemical composition of S. is subject to daily fluctuations.

Considerable age differences of mineral composition S. Tak are described, e.g., with age as a part of a secret of a parotid gland of the person the level of chlorine decreases and several times the amount of calcium increases that matters for formation of a dental and salivary calculus (see. Dental calculus , Sialolithiasis ), and also activities of enzymes C. and content in it of amino acids and carbohydrates.

S.'s players are changed also at a number of diseases. At a diabetes mellitus (see. diabetes mellitus ) the amount of glucose in the mixed S. increases, but nevertheless it is many times less, than in blood. At the nephrite which was complicated by uraemia the amount of residual nitrogen considerably increases in S. that is used for diagnosis of this pathology at small children. At patients with arterial hypertension in S. concentration of cyclic AMF is increased.

The page as the main source of receipt in enamel of tooth of calcium, phosphorus and other mineral elements influences physical and chemical properties of enamel of tooth, including resistance to caries (see. Caries of tooth ). Changes of quantity and chemical structure of S. have pathogenetic value in development of caries. At sharp and long restriction of secretion of S., napr, at xerostomias (see), snowballing of caries of teeth is observed, the cariogenic situation is created by low speed of secretion of S. during sleep. At caries note big lability of chemical structure of S. with increase in anaerobic glycolysis. It is found at functional loads, napr, at a peroralnompriyema of sucrose with its temporary delay in a mouth. However inconsistency of these different researchers does not allow to speak convincingly about natural changes of activity of alpha amylase, phosphatases and some other enzymes, and also contents of calcium and phosphorus in S. at caries of teeth. The reasons of contradictions, probably, are in age and specific differences, in features of stimulation of salivation, character of the previous meals, that S. receive at different times days, without taking into account at the same time conditions of c. N of page.

At periodontosis (see) depending on a form of a disease in S. the maintenance of a lysozyme, inhibitors of proteinases decreases, activity of system of proteolytic enzymes, alkaline and acid phosphatases increases, the content of immunoglobulins changes. These changes have pathogenetic value in development of periodontosis.

Saliva in the medicolegal relation. For the solution of questions of identification in investigative practice quite often happens it is necessary to establish existence, group and a sex of S. on material evidences (see) — stubs, post envelopes, ware, clothes, etc. For approximate judgment of S.'s presence on this or that subject it is investigated in UF-light (S.'s spots give a whitish luminescence).

S.'s presence on material evidences is established at detection in the studied material of alpha amylase. The method of definition of enzyme is based on starch hydrolysis by amylase to products (oligosaccharides) which are not giving coloring with solution of iodine (see. Volgemuta method ).

Establishment of group accessory of S. on the AB0 system is made by means of reaction of absorption. Judgment of possible accessory of S. to a certain person is carried out taking into account the so-called phenomenon of a vydelitelstvo (see. Medicolegal laboratory researches ). Definition of a sex of S. is possible on the cells of an epithelium of a mucous membrane of an oral cavity which are contained in it (see. Sex chromatin ).

Bibliography: Barsegyants L. O. and Levchenkov B. D. Forensic medical examination of allocations of an organism, page 50, M., 1978; Bohr E. V. and L e at with P. A. Kariyes of teeth, M., 1979; To and z and A. I. m, In about l about x about and - Skye L. I. and Goloborod ý-to about O. P. Definition of activity of enzymes in secrets of sialadens and a mucous membrane of a nose, in book: Enzymes in otorinolar., under the editorship of K. N. Veremeenko, page 164, Kiev, 1980; P. N Jambs. Isoantigens and isoantibodies of the person it is normal also of pathology, M., 1974; Leontyev V. K. and Petroviç Yu. A. Biochemical methods of a research in clinical and experimental stomatology, Omsk, 1976; Yrokhonchu-kov A. A., Loginova N. K. both and and N and N. A. Functional diagnosis in dental practice, M., 1980; Tumanov A. K. Bases of forensic medical examination of material evidences, page 272, M., 1975; Physiology of gisto-gematichesky barriers, under the editorship of Ya. A. Rosina, etc., page 353, M., 1977; Physiology of digestion, under the editorship of A. V. Solovyov, etc., page 136, L., 1974; Chauncey H. N of Salivary enzymes, J. Amer. dent. Ass., at. 53, p. 360, 1961; Jenkins G. N. The physiology and biochemistry of the mouth, Oxford a. o., 1978; Kroncke A. Freie Zucker im menschlichen Niichtern-speichel und deren Beziehungen zur Zahn-karies, Lpz., 1959; Shannon I. L., S u d d i with k R. P. a. Dowd F. J. Saliva, composition and secretion, Basel a. o., 1974; Young J. A. a. Schneyer C. A. Composition of saliva in mammalia, Aust. J. exp. Biol., v. 59, p. 1, 1981.

Yu. A. Petroviç; Century V. Tomilin (court.).