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

نویسندگان

  • A Dzurba
  • N Vrbjar
  • A Breier
  • A Ziegelhöffer
چکیده

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.

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عنوان ژورنال:
  • General physiology and biophysics

دوره 15 1  شماره 

صفحات  -

تاریخ انتشار 1996