Effect of spermine on kinetic characteristics of ATP-hydrolase systems of the uterus myocyte plasma membranes

The paper deals with the activation effect of aliphatic polyamine spermine (1 mM) on the enzymatic activity of ouabain-sensitive Na+,K(+)-ATPase and the ouabain-resistant basal Mg(2+)-ATPase in the suspension of the myometrium cell plasma membranes treated with 0.1% digitonin solution. It was found...

Full description

Saved in:
Bibliographic Details
Published inUkrains'kyi biokhimichnyi zhurnal (1999 ) Vol. 80; no. 4; p. 42
Main Authors Veklich, T O, Shkrabak, O A, Kosterin, S O
Format Journal Article
LanguageUkrainian
Published Ukraine 01.07.2008
Subjects
Adenosine Triphosphate - metabolism
Animals
Ca(2+) Mg(2+)-ATPase - metabolism
Cell Membrane - drug effects
Cell Membrane - enzymology
Cells, Cultured
Female
Kinetics
Myometrium - cytology
Myometrium - drug effects
Myometrium - enzymology
Sodium-Potassium-Exchanging ATPase - metabolism
Spermine - pharmacology
Swine
Online AccessGet more information

Cover

More Information
Summary:The paper deals with the activation effect of aliphatic polyamine spermine (1 mM) on the enzymatic activity of ouabain-sensitive Na+,K(+)-ATPase and the ouabain-resistant basal Mg(2+)-ATPase in the suspension of the myometrium cell plasma membranes treated with 0.1% digitonin solution. It was found that spermine increased the enzymatic Na+,K(+)-ATPase activity without disrupting of its dome-shaped dependence on the ratio of [Na+]/ [K+] in isotonic condition. The constants of the enzyme activation by Na+ and K+ ions did not vary. Spermine also did not change the character of dependence of Na+,K(+)-ATPase and Mg(2+)-ATPase activity on the concentration of MgCl2 (0.1-2 mM) and on the concentration of ATP (0.05-1 mM). In this case the affinity for the corresponding compounds did not also vary. Thus, the activation by spermine occurred mainly due to enlargment of enzyme "turnover number" according to V(max) increase. It is expected that the obtained experimental data can be important for further investigations of regulation mechanisms of Na+,K(+)-ATPase and Mg(2+)-ATPase activity and also mechanisms of cations exchange control in the smooth muscles.