[Effect of nitrogen and oxygen active compounds on exchange of Ca2+ and H+ through the myometrial cell membrane].
While using myometrium sarcolemma vesicles the action of sodium nitroprusside, NO2-, NO3- and H+ on delta pH-dependent Ca(2+)-transport and passive permeability for H+ vesicles sarcolemma was estimated in the wide concentration range (10(-10)-10(-3) M) of the substances tested. In order of studying calcium transport 45Ca2+ was used, while for H+ translocation registrating via sarcolemma delta pH-indicator 14C-methylamine was applied. Sodium nitroprusside was displayed as weakly effective, while nitrite-anions essentially increased delta pH-dependent Ca2+ transport in the physiologically significant nanomolar concentration region, however in the micromolar region these substances effect failed to differ from the control and restored its intensity starting at 10(-4) M and more. Under the experiment sodium nitroprusside produces considerable quantities of NO2-. Effectory action of NO3- was similar as of NO2-. In the micromolar region the compounds estimated increased considerably sarcolemma passive permeability for H+. Hydrogen peroxide decreased delta pH-dependent Ca(2+)-transport by 10(-8) M and 10(-3) M while at the concentration equal to 10(-3) M increased the sarcolemma passive permeability for proton. Sodium nitroprusside and NO2(-)-effect on the vesicles passive permeability for proton failed to be prevented by dithiotriitol, while H2O2 action was completely removed. The conclusion about the complex concentration-dependent character of the active oxygen metabolities to the sarcolemma transport processes was made, and it's noticeable that the important role in vivo, probably could be played by NO (NO2-) stable nitric metabolities.
Danylovych
Iu V
IuV
Palladin Institute of Biochemistry, NAS of Ukraine, Kyiv. kinet@biochem.kiev.ua
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D005260:Female; D006859:Hydrogen / Q000378:metabolism*; D009215:Myometrium / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D013552:Swine
D006859:Hydrogen; D009584:Nitrogen; D010100:Oxygen; D002118:Calcium