[The reactivity of liver monoamine oxidase in the ringed seal Phoca hispida ladogensis].

The goal of the work consisted in study of substrate and inhibitor specificity of liver monoamine oxidase (MAO) of the freshwater Ladoga subspecies of the ringed seal Phoca hispida ladogensis. The studied enzyme has been established to have large substrate specificity by deaminating, apart from eight classic substrates of MAO of terrestrial mammals, also histamine, the diamine oxidase substrate. It is found out that the deamination rates of benzylamine, beta-phenylethylamine, and N-methylhistamine almost one order higher than rates of deamination of serotonin and noradrenaline. MAO of the seal liver does not deamnate putrescine and cadaverine and is not sensitive to 10(-2) M semicarbazide. We calculated bimolecular constants of interaction rates of inhibitors chlorgiline, deprenyl, berberine, sanguinarine, chelidonine, and four derivatives of acridine with the enzyme at deamination of nine substrates. By the method of the substrate-inhibitor analysis, we showed the enzyme heterogeneity, i. e., the existence in the seal liver of at least two different MAO.

[Liver monoamine oxidase activity of the lamprey Lampetra fluviatilis. the substrate-inhibitory specificity].

Based on data of substrate-inhibitory analysis with use of specific inhibitors--deprenyl, chlorgi-lin--and specific substrates--serotonin, noradrenalin, benzylamine, beta-phenylethylamine, and N-methylhistamine--a suggestion is put forward about the possible existence of one molecular form of monoamine oxidase (MAO) in liver of mature individuals of the European lamprey Lampetra fluviatilis. There are determined kinetic parameters of monoamine oxidase deamination of eight substrates, which indicates the large spectrum of substrate specificity of the lamprey liver MAO. The studied enzyme does not deaminate histamine and putrescine and is not sensitive to 10(-2) M semicarbaside. Results of study of the substrate-inhibitor specificity allow us to suggest some resemblance of catalytic properties of the lamprey liver MAO and the mammalian form A MAO. The revealed low activity of the enzyme at deamination of all used substrates seems to be connected with low detoxational functional of the lamprey liver.

[Comparative enzymological study of catalytic properties of sturgeon fish liver monoamine oxidases].

We performed comparative study of substrate and inhibitor specificity of liver monoamine oxidases (MAO) of the giant sturgeon Huso huso, starred sturgeon Asipenser stellatus, Persian sturgeon Asipenser persicus, and Russian sturgeon Asipenser gueldenstaedtii. Results of the substrate-inhibitor analysis with use of inhibitors chlorgilin and deprenil, as well as of five specific substrates indicate homogeneity of these enzymes. All studied MAO have several orders higher sensitivity to chlorgilin than that to deprenil, the essential interspecies differences being observed. There are determined kinetical parameters of enzymatic deamination (K(M) and V) of tyramine, serotonin, noradrenalin, benzylamine, beta-phenylethylamine, and N-methylhistamine. It is found that all studied enzymes show the higher activity toward serotonin and noradrenalin--substrates of the MAO form A, as compared with benzylamine, beta-phenylethylamine, and N-methylhistamine--substrates of the MAO form B of mammals, the maximal activity being shown by enzyme of the giant sturgeon.

[Substrate-inhibitory analysis of monoamine oxidase from hepatopancreas of the octopus Bathypolypus arcticus].

Study of the substrate-inhibitory specificity of mitochondrial monoamine oxidase (MAO) of hepatopancreas of the octopus Bathypolypus arcticus revealed distinctive peculiarities of catalytic properties of this enzyme. The studied enzyme, on one hand, like the classic MAO of homoiothermal animals, is able to deaminate tyramine, serotonin, benzylamine, tryptamine, beta-phenylethylamine, while, on the other hand, deaminates histamine and does not deaminate putrescine--classic substrates of diamine oxidase (DAO). Results of the substrate-inhibitory analysis with use of chlorgiline and deprenyl are indirect proofs of the existence in the octopus hepatopancreas of one molecular MAO form. Semicarbazide and pyronine G turned out to be weak irreversible inhibitors, four derivatives of acridine--irreversible inhibitors of the intermediate effectiveness with respect to the octopus hepatopancreas MAO; specificity of action of inhibitors at deamination of different substrates was equal.

[Catalytic characteristics of monoamine oxidase of whitefish Coregonus lavaretus ludoga].

Study of substrate-inhibitory specificity of liver mitochondrial monoamine oxidase (MAO) of sexually mature individuals of the whitefish Coregonus lavaretus ludoga P. from the Ladoga Lake has revealed distinguished peculiarities of catalytical properties of this enzyme. The studied MAO, on one hand, like the classical enzyme of homoiothermal animals, is able to deaminate tyramine, serotonin, benzylamine, tryptamine, and beta-phenylalanine, but, on the other hand, to deaminate histamine, the classic substrate of diamine oxidase. The found equal activity and sorptional ability of the enzyme toward six studied substrates including histamine, as well as results of the substrate-inhibitory analysis with use of specific inhibitors--deprenyl and chlorgilin--indicate homogeneity of the enzyme. The detected for the first time among the fish MAO wide substrate specificity and an unusually low sensitivity to both studied acetylene inhibitors does not allow ascribing unanimously the studied enzyme to the known MAO forms of organs and tissues of homoiothermal organisms. Apparently, the revealed enzyme form of poikilothermal organism is not the true MAO, but performs a large amine oxidase function.

[Comparative sensitivity of liver monoamine oxidases of frog and whitefish to some tricyclic compounds].

There is performed a comparative analysis of action of four acridine derivatives and of one xanthene derivative (pyronine G) on activity of liver monoamine oxidase (MAO) of two species of poikilothermal freshwater animals: a representative of amphibians--the common frog Rana temnporaria and a representative of the order Salmonidae--the European whitefish Coregonus lavaretus. The studied synthetic hexamerous tricyclic compounds show the irreversible character of inhibition of intermediate potency towards the enzyme from both biological sources. There are obtained qualitative and quantitative differences in the reactional ability and selectivity of action of the studied inhibitors for liver MAO of frog and whitefish. The obtained data of the inhibitory analysis with use of specific substrates are an indirect proof for the existence in liver of the studies frog species of two molecular forms, whereas in the whitefish liver--single molecular MAO form.

[Comparative substrate-inhibitor analysis of liver monoamine oxidases of minks].

Comparative substrate-inhibitor analysis of catalytic properties of liver monoamine oxidases (MAO) was performed in the mature males of the American mink Mustela vison and the European mink Mustela lutreola. The action on the MAO activity was studied of alkaloids of the benzo[c]phenanthridine group: sanguinarine and chelidonine, diisoquinoline alkaloid berberine, medication agents Ukrain and Sanguirythrin as well as derivatives of 2-propylamine: deprenyl and clorgylin. The latter turned out to be irreversible inhibitor of the MAO A form, whereas deprehyl--irreversible inhibitor of the MAO B form in both studied mink species. The selectivity of action of each inhibitor on the corresponding liver MAO form for the species M. vison was one order of magnitude stronger than for the species M. lutreola. All studied alkaloids as well medication agents on their basis have been shown to be specific irreversible inhibitors of the intermediate strength of the liver MAO A form of both mink species. They inhibit the enzymatic deamination of serotonin, tyramine, and tryptamine without affecting the deamination reaction of benzylamine and beta-phenylethylamine (at concentrations of 10 mM and lower). Out of the studied five isoquinoline agents, the medication Ukrain and alkaloid chelidonine have the highest inhibitory action; the agent Sanguirythrin and alkaloids berberine and sanguinarine produce the weaker monoamine oxidase effect. The revealed specificity of action of the studied inhibitors is an indirect evidence for the presence in the liver enzymes of both mink species, like in the rat liver enzyme, of several molecular forms.

[Comparative enzymological study of catalytic properties of liver monoamine oxidases in frogs].

Comparative enzymological study of catalytical properties of monoamine oxidase (MAO) of liver of the lake frog Rana ridibunda and brown frog Rana temporaria has revealed certain features of similarity and differences between these enzymes. The MAOs from both studied biological sources show catalytic properties resembling those of the classical MAO of terrestrial vertebrates: they deaminate tyramine, tryptamine, serotonin, benzylamine and do not deaminate histamine, have sensitivity to chlorgiline, the specific inhibitor of the MAO A form, and deprenyl, the specific inhibitor of the MAO B form, and are not inhibited with 10(-2) M semicarbazide. Based on data of substrate-inhibitor analysis, a suggestion is put forward about the existence of two molecular forms of the enzyme in liver of the studied frog species. Interspecies quantitative differences have been revealed between liver MAO of Rana ridibunda and Rana temporaria in values of kinetic parameters of reactions of deamination of several substrates and in sensitivity to the inhibitors, deprenyl and clorgyline. In the species Rana temporaria the MAO activity in reaction of deamination of serotonin and benzylamine were practically identical, whereas in the species Rana ridibunda these parameters for serotonin were almost one order of magnitude higher than for benzylamine. For the species Rana ridibunda, selectivity of action of deprenyl was expressed many times weaker while selectivity of the chlorgiline--one order of magnitude stronger than for the species Rana temporaria. The catalytic activity for all studies substrates of liver MAO of both studied amphibian species were several times lower as compared with the enzyme of rat liver.

[Comparative study of substrate and inhibitory specificity of monoamine oxidase in the optic ganglia of squids].

Comparative study of substrate specificity of monoamine oxidase (MAO) of optic ganglia of the Pacific squid Todarodes pacificus and the Commander squid Berryteuthis magister has been carried out. The enzyme of the Pacific squid, unlike that of the Commander squid, has been established to be able to deaminate not only tyramine, tryptamine, serotonin, benzylamine, and beta-phenylethylamine, but also histamine--substrate of diamine oxidase (DAO). In relation to all studied substrates, the MAO activity of optic ganglia of T. pacificus is several times higher as compared with B. magister. In the case of deamination of serotonin this difference was the greatest and amounted to 5 times. Semicarbazide, the classic DAO inhibitor, at a concentration of 10 mM did not inhibit catalytic activity of both studied enzymes. The substrate-inhibitory analysis with use of deprenyl and chlorogiline, specific inhibitors of different MAO forms, indicates homogeneity of the enzyme of the Pacific squid and heterogeneity of the Commander squid enzyme whose composition seems probably to contain at least two MAO forms. There are obtained quantitative differences in substrate specificity and reaction capability with respect to the inhibitors chlorgiline and deprenyl for MAO of optic ganglia of the studied squid species. These differences probably can be explained by significant differences in the evolutionary level of these biological species.

[Catalytical properties of the liver monoamine oxidases of the commander squid Berryteuthis magister from various habitation zones].

A detailed kinetic analysis is performed of enzymatic reactions of deamination of tyramine, tryptamine, serotonin, benzylamine, beta-phenylethylamine, and histamine under action of liver monoamine oxidase (MAO) of the Commander squid Berryteuthis magister from various habitation zones in the Bering and Japan Seas. There has been revealed a substrate inhibition by high concentrations of all studied substrates, which seems to indicate mutual effect of various MAO forms present in liver of the studied squids. Analysis of kinetic parameters of enzymatic reactions of deamination of six studied substrates and the substrate-inhibitory analysis with use of two derivatives of acridine and deprenyl indicate the enzyme heterogeneity, the presence of at least two MAO forms and the absence of intraspecies differences in MAO of the Commander squids from various habitation zones. The most active was the MAO form responsible for serotonin deamination. There were obtained quantitative difference in substrate specificity and reaction ability with respect to inhibitor of proflavin for the liver MAO of the Commander and Pacific squids.

[Comparative study of catalytic properties of mink and rat liver monoamine oxidase].

Comparative substrate-inhibitor analysis of catalytic properties of monoamine oxidase (MAO) of liver mitochondrial of the American mink Mustela vison Schreber and of liver of Wistar rat has been performed. It has been established that MAO of mink, like MAO of rat, has properties of classic mammalian MAO: it deaminates tyramine, tryptamine, serotonin, benzilamine, beta-phenylethylamine and does not deaminate histamine as well as does not have sensitivity to semicarbazide. Study of kinetics of monoamine oxidase deamination has allowed revealing both qualitative and quantitative differences between these enzymes. Specificity of action on MAO, form A, of four irreversible inhibitors--acridine derivative--has been established; the specificity for the mink liver MAO was several times higher than for the rat liver MAO. It is suggested that liver MAO of both species of the studied animals has several isoenzyme forms or several centers of substrate binding.

[Characteristics of the brain system activity and vegetative function formation in children under conditions of the European north (a problem study)].

Results of complex medical-physiological research performed during 10 scientific expeditions in Arkhangelsk region in 2003-2005 are presented. Influence of climatic-geographic, biogeochemical and social conditions of North-West region of Russia on sexual maturation, formation of the brain structural-functional organization, vegetative functions, immunological and biochemical status of schoolchildren was studied with the aid of modern neurophysiologic (computer electroencephalography, computer rheoencephalography, computed electric dipole origin tomography, etc.), psychophysiological and psychometric methods (evaluation of cognitive and mnestic functions, Vechsler 1Q estimation), biochemical assessment of monoamine oxidase and butyrylcholinesterase activity, physical-chemical analysis of macro- and microelements in the organism.

[Effect of some isoquinoline alkaloids on enzymatic activity of acetylcholinesterase and monoamine oxidase].

It has been shown, that some benzo[c]-phenanthridine and diisoquinoline alkaloids isolated from Chelidonium majus L. and Macleaya (Bocconia) cordata and M. microcarpa (berberine, sanguinarine, chelidonine) and of drugs ("Ukrain" and "Sanguirythrine") inhibited the enzyme activity of acetylcholinesterase from human erythrocyte and monoamine oxidase from the rat liver. All agents under study have been shown to be reversible inhibitors of the enzymatic hydrolysis of acetylthiocholine. It has been determined that chelidonine belonged to reversible inhibitors of a competitive type, all other examined agents have been demonstrated to be inhibitors of a mixed competitive-noncompetitive type, and a greater contribution to the inhibition was made by the competitive constituent. Among all examined agents berberine, sanguinarine and "Sanguirythrine" were the strongest inhibitors of this reaction and chelidonine and "Ukrain" were much weaker. All agents under study have been shown to be irreversible inhibitors of the oxidative deamination reaction of serotonine and tyramine and not to influence the oxidative deamination reaction of benzylamine as a substrate. Among the examined agents, alkaloid sanguinarine and drug "Ukrain" are the strongest inhibitors of the reaction, alkaloids berberine, sanguinarine and "Sanguirythrine" exhibit a weaker action.

[Inhibition of liver mitochondrial monoamine oxidase activity by alkaloids isolated from Chelidonium and Macleaya and by their derivative drugs]. / Ingibirovanie aktivnosti mitokhondrial'noi monoaminoksidazy alkaloidami iz chistotela i makleii i lekarstvami na ikh osnove.

It has been shown that the major alkaloids from plants Chelidonium majus L. and Macleaya (Bocconia) cordata and microcarpa, namely, berberine, sanguinarine, chelidonine, and drugs "Ukrain" (thiophosphoric acid derivative of a sum of the alkaloids isolated from Ch. majus L.) and "Sanguirythrine" (a mixture of the alkaloids sanguinarine and chelerythrine, w/w 3:7, isolated from Macleaya), are irreversible inhibitors of oxidative deamination reaction of serotonin and tyramine as substrates, catalyzed by rat liver mitochondrial monoamine oxidase (MAO). At the same time these substances do not influence the oxidative deamination reaction of benzylamine as substrate (in concentration 1 mM or less). The substrate specificity of this inhibition manifests that mainly the oxidative deamination reactions catalyzed by MAO form A are inhibited by the agents studied. Among the examined agents, alkaloid chelidonine and drug "Ukrain" are the strongest inhibitors of the reaction. Alkaloids berberine and sanguinarine and drug "Sanguirythrine" exhibit a weaker action. Judging from the data obtained, sanguinarine and chelerythrine appear to exert similar inhibitory effects in this reaction, since sanguinarine and "Sanguirythrine" have similar values of bimolecular rate constants of their interaction with mitochondrial MAO. As it is well known, the MAO inhibitors appear to be, as a rule, pronounced antidepressants. The combination of malignotoxicity and antidepressive activity in drug "Ukrain" seems to be favourable for its clinical applications.

[A new method of preparing and some properties of high molecular weight monoamine oxidase from swine liver mitochondria]. / Novyi sposob polucheniia i nekotorye svoistva vysokomolekuliarnoi monoaminoksidazy iz mitokhondrii pecheni svin'i.

Isolation of highly purified and highly molecular monoamine oxidase (MAO) from pig liver mitochondria have been worked out. Specific activity of isolated preparation is 2700 times higher than of original mitochondria homogenate. Enzyme solubilization by digitonin, affinity chromatography purification and ultrafiltration underlie this method. MAO catalytic properties changing during the process of purification by different methods have been investigated. Substrate specificity was studied; kinetic parameters of enzymatic desemination were calculated.