From Big Medical Encyclopedia

NITROZOAMINY, NITROZOAMIDY — the nitroso compounds possessing strong oncogenous action.

Constitutional formula:

where R1 and R2 — alkyl, aryl or acyl groups.

Oncogenous action on the person finally is not proved, but, on a nek-eye to data, very possibly.

Except oncogenous, they possess toxic action of hl. obr. on a liver; nitrozoamida work also radomimetically, and nek-ry of them are the strongest of the known mutagens (see. Nitrozoalkilmochevina ). Thanks to cytotoxic action nek-ry nitrozoamida, napr, nitrozometilmochevina (see), etc., use for treatment of malignant tumors.

Nitrozoamina and a nitrozoamida are used in the industry as initial products by production of nek-ry types of fuel as antioxidants, solvents, etc.

Oncogenous effect of N-nitrozo-dimethylamine (dimethylnitrosamine) on a liver of rats was established in 1956. Magee and Barnes (R. of N. Magee, J. M of Barnes). In 1964 F. Ender and soavt, reported about existence in the fish meal processed by saltpeter, a N-nitrozodimetila-mine (NDMA), caused mass death of sheep. Later flying nitrozoamina were found in various foodstuff. In further NDMA, and also N-nitrozopirrolidin, N-nitrozo-diethyl amine (NDEA) and N-nitrozopi-peridin were found in 10 — 30% of the studied tests of salty and smoked meat and fish products in concentration to 10 mkg/kg. Culinary processing of nek-ry foodstuff can promote increase in amount of these substances in them. Nitroso compounds find in air of nek-ry production rooms, in tobacco smoke, and also in gastric contents, blood and urine.

Flying nitrozoamina have an appearance of oily liquids with t ° more often kip 150 — 250 °, yellow color, a rastvorima in water, organic solvents and lipids. They are sensitive to ultraviolet rays and decay under their action. At the room temperature and in the dark they are rather resistant, especially in neutral and alkaline condition. Nitrozoamida are hydrolyzed and easily enter chemical reactions with various connections.

In an organism of a nitrozoamina are exposed to metabolic activation by microsomal oxidases, nitrozoamida are quickly hydrolyzed in the alkylating metabolites reacting with nucleophilic groups of macromolecules (DNA, RNA, a squirrel) cells.

In experiences on a lab. animals more than 100 nitrozoampn and nit-rozoamid are studied, at the same time 80% have them the expressed oncogenous effect. NDMA causes development of malignant tumors in 16 types, and NDEA — in 26 animal species. By selection of these oncogenous substances at a certain look a lab. animals it is possible to cause purposefully development of tumors as on site administrations of drug, and in various bodies — a gullet, a prestomach, a ferruterous stomach, a liver, intestines, a pancreas, a trachea, bronchial tubes, lungs, kidneys, a bladder, an ovary, a uterus, c. N of page, skin, hemopoietic bodies, etc. Their organotropic oncogenous action, as a rule, does not depend on a way of introduction, but the lab can change depending on a dose and a look. animals. E.g., at rats the daily dose of NDEA of 75 mkg/kg in hron, experiences causes tumors of a liver, and a single dose of 1,25 mg/kg — tumors of kidneys.

Many nitrozoamina and nitrozo-amides after introduction by a pregnant animal can cause tumors in posterity that explain them with transplacental action.

Important feature of these substances is ability to be formed in the environment and in an organism as a result of a nitrozation of nitrites and nitric oxides, secondary and basic nitriles or amides (urea, a carbamate, guanidine, etc.). Nitrozation can be promoted by the microorganisms of an oral cavity, stomach (especially at the raised pH) having nitrate-re duktazny activity. For reduction of formation of nitrozo-amines and nitrozoamid in an organism it is necessary to limit receipt with food and water of nitrates, nitrites, and also nitroziruyushchikhsya amines and amides. Nek-ry substances, napr, ascorbic and gallic to - you, a tannin and some other, promote an ingibition of process of a nitrozation.

The main methods of identification of nitrozoamin and nitrozoamid are massspektrometriya (see), gas and liquid chromatography (see).

During the work with N., N it is necessary to observe precautionary measures.

See also Oncogenous substances .

Bibliogr. Bogovsky P. A. Geogpgiyennches * • «•» * N-nitrozosoyedp-neny value. in iir, - Plants and chemical carcinogens. l-d of an edition of E. I. Slepyan, page 16:3, JI., 31 gee P. N. and In and - nes J. M. Kantserogennye nptrozogoye-dinenpya, in book: Usp. in izuch. cancer, under the editorship of L. M. Shabad, t. 10, page 242, M., 1971; F r and d m and JI L., m at x and m of e of t-sh and F. M. N both To about in and to about in S. S. Achievements of chemistry H-iitrozaminov aliphatic series. Usp. chemical, t. 40, century 1, page 64, 107 1. bibliogr.; B of nder F. and. the lake of Isolation ap (} identification of a hepatotoxic factor in Mtiiuj meal produced from .sodium nitrite prc-erv rd herring, Naturwissenschai-ten, Bu - i>. 037, 1964; Environmental aspecl-ot \-nitroso compounds, ed. by E. A. Walker a. o. Lyon, 1978; P r e u s s-m a nn K. Chemische Carcinogene in der menschlichen Umwelt, Handb, allg. Path., hrsg. v. H. - W. Altmann u. a., Bd 6, T. 6, S. 421, B. u. a., 1975.

P. A. Bogovskip.