title: [Effect of nitric oxides and hydrogen peroxide on Ca2+, Mg(2+)-ATPase and Mg(2+)-ATPase activity in myometrium sarcolemma].
abstract: The action of sodium nitroprusside, nitrite-anions and hydrogen peroxide on Ca2+, Mg(2+)-ATPase and Mg(2+)-ATPase (Ca(2+)-independent) enzymatic activity in myometrium sarcolemma fraction is investigated. It is established, that 0.1 mM sodium nitroprusside and 10(-8)-10(-5) M nitrite-anions essentially reduce Ca2+, Mg(2+)-ATPase activity whereas Mg(2+)-ATPase proved to be absolutely resistant to them. At rather high concentration of nitrite-anions (0.1 mM) appreciable stimulation of Ca2+, Mg(2+)-ATPase was observed. Hydrogen peroxide (10(-8)-10(-4)), depending on the concentration suppressed both enzymes activity. However, Ca2+, Mg(2+)-ATPase proved to be more sensitive to the action of H2O2 (seeming K(i) = 0.42 +/- 0.1 microM), than Mg(2+)-ATPase (seeming K(i) = 3.1 +/- 0.9 microM). At presence of 1 mM ditiothreitole (a reducer of SH groups of the membrane surface) action of investigated substances considerably decreased. Reagents on carboxic- (dicyclogexilcarbodiimid) and amino- groups of the membrane (trinitrobenzolsulfonic acid) inhibited both Ca2+, Mg(2+)-ATPase, and Mg(2+)-ATPase activity in membrane fractions. In the presence of noted reagents sodium nitroprusside and nitrite-anions action was not almost shown. Hence, nitrogen oxide, nitrite-anions and hydrogen peroxide suppress Ca2+, Mg(2+)-ATPase and Mg(2+)-ATPase (only hydrogen peroxide) activity in the plasmatic membrane of myometrium cells, and this action can be connected with direct updating of superficial chemical groups of the membrane.
authors.forename: H V
authors.initials: HV
authors.lastname: Danylovych
authors.forename: Iu V
authors.initials: IuV
authors.lastname: Danylovych
mesh_terms: D000818:Animals; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D066298:In Vitro Techniques; D009215:Myometrium / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D020030:Nitric Oxide Donors / Q000494:pharmacology*; D009573:Nitrites / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology; D012508:Sarcolemma / Q000187:drug effects* / Q000201:enzymology; D013552:Swine
chemical_list: D020030:Nitric Oxide Donors; D009573:Nitrites; D009599:Nitroprusside; D006861:Hydrogen Peroxide; D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases