The membrane effect of benfluron: modulation of the heart sarcolemmal (Na+, K+)-ATPase and Mg(2+)-ATPase activities

Gen Physiol Biophys. 1996 Feb;15(1):71-5.

Abstract

The effect of Benfluron on the heart sarcolemmal (Na+, K+)-ATPase and Mg(2+)-ATPase activities was studied in crude membrane fraction as well as in purified sarcolemmal membranes isolated from rat heart. Benfluron in concentration range 10(-7) -5 x 10(-5) mol.l-1 did not exert any effect on ATPase activities studied. 10(-4) mol.l-1 Benfluron was stimulatory towards (Na+, K+)-ATPase, while Mg(2+)-ATPase activity was depressed. Kinetic analysis of interaction of Benfluron with (Na+, K+)-ATPase revealed an increase in the Vmax and decrease in the K(m) values for ATP. The possible mechanism of interaction of the drug with (Na+, K+)-ATPase is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Ca(2+) Mg(2+)-ATPase / antagonists & inhibitors
  • Ca(2+) Mg(2+)-ATPase / metabolism*
  • Dose-Response Relationship, Drug
  • Enzyme Inhibitors / pharmacology
  • Fluorenes / administration & dosage
  • Fluorenes / pharmacology*
  • Heart / drug effects*
  • In Vitro Techniques
  • Kinetics
  • Myocardium / enzymology
  • Rats
  • Sarcolemma / drug effects
  • Sarcolemma / enzymology
  • Sodium-Potassium-Exchanging ATPase / metabolism*

Substances

  • Enzyme Inhibitors
  • Fluorenes
  • VUFB 13468
  • Ca(2+) Mg(2+)-ATPase
  • Sodium-Potassium-Exchanging ATPase