[TETRAMETHONIUM DERIVATIVES AS REVERSIBLE INHIBITORS OF DIFFERENT CHOLINESTERASES].

To study the influence of onium atom nature on anticholinesterase efficiency of elementorganic derivatives of tetramethylenbisonium compounds as reversible inhibitors of cholinesterase (ChE) - acetyl-ChE from human erythrocytes, butyryl-ChE from horse serum, ChE from the brain of frog Rana temporaria and ChEs from visual ganglia of Pacific squid Todarodes pacificus and individuals of Comman- der squid Berryteuthis magister from different habitats in the northwestern Pacific Ocean were investigated. Bisphosphonium inhibitors were significantly more potent effectors than bisammonium ones, but this may be associated with a significantly increased size and hydrophobicity of onium groups of the former. Bisammonium organosilicon compound and its monoammonium analogue were equally active reversible ChE inhibitors in mammals. First studied bis(phenyliodonium) derivative, which is characterized by a significant increase in the degree of hydrophobicity due to introduction of fluorine atoms in the interonium tetramethylene chain, also had marked anticholinesterase effects on mammalian ChE.

[COMPARATIVE SENSITIVITY OF CHOLINESTERASES IN VERTEBRATES AND INVERTEBRATES TO HIGHLY SPECIFIC ORGANOPHOSPHORUS INHIBITORS DIISOPROPYL FLUOROPHOSPHATE (DFP) AND (2-ETHOXYMETHYL PHOSPHORYL THIOETHYL) ETHYL (METHYL) SULPHONIUM SULPHOMETHYLAT (GD-42)].

The review presents data on comparative reactivity of 68 cholinesterase preparation from various organs and tissues in a number of vertebrates and invertebrates based on sensitivity to two highly specific and most studied organophosphorus inhibitors--diisopropyl fluorophosphates (DFP) and (2-ethoxymethyl phosphoryl thioethyl) ethyl (methyl) sulphonium sulphomethylat (GD-42). Analysis of these data suggests a great diversity in enzymologic characteristics of cholinesterase preparation in representatives of vertebrates and invertebrates, this variety observed even for closely related enzymes in animals of almost the same level of development.

[Transferase activity of horse blood serum cholinesterase at hydrolysis of 1-methyl-8-acetoxychinolium iodide in the presence of aliphatic alcohols].

To check whether the horse blood serum butyrylcholinesterase expresses transferase activity at the complex ester hydrolysis in the presense of several low-molecular aliphatic alcohols, a study was performed with aid of the chromogenic substrate 1-methyl-8-acetoxychinolium whose phenolic hydrolysis product absorbs intensively at 445 nm, whereas the initial ester in this specter area practically does not absorb. This allowed measuring simultaneously the products of accumulation of both products of enzymatic hydrolysis: of acetic acid by the potentiometric, while of phenol--by the photometric method. Rates of formation of both products of enzymatic hydrolysis are practically equal in experiments with all studied alcohols. This indicates that horse blood serum butyrylcholinesterase under these experimental conditions does not catalize transfer of acetyl residue to the studied aliphatic alcohols, i. e. does not have transefase activity.

[Ligands of cholinesterases of ephedrine and pseudoephedrine structure].

The paper is a review of literature data on interaction of the mammalian erythrocyte acetylcholinesterase and blood serum butyrylcholinesterase with a group of isomer complex ester derivatives (acetates, propionates, butyrates, valerates, and isobutyrates) of bases and iodomethylates of ephedrine and its enantiomer pseudoephedrine. For 20 alkaloid monoesters, parameters of enzymatic hydrolysis are determined and their certain specificity toward acetylcholinesterase is revealed, whereas 5 diesters of iodomethylates of pseudoephedrine were hydrolyzed only by butyrylcholinesterase. The studied 20 aklaloid diesters and 10 trimethylammonium derivatives turned out to be non-competitive reversible inhibitors of acetylcholinesterase and competitive inhibitors of butyrylcholinesterase. The performed for the first time isomer and enantiomer analysis "structure-efficiency" has shown that in most cases it is possible to state the greater comlementarity of the catalytical surface of enzymes for ligands of the pseudoephedrine structure, such differentiation being realized more often at the reversible inhibition of enzymes. pseudoephedrine.