Modulation of the Ca2+- or Pb2+-activated K+-selective channels in human red cells. II. Parallelisms to modulation of the activity of a membrane-bound oxidoreductase.
Modulation of Ca2+-activable K+ permeability was compared with modulation of a membrane-bound oxidoreductase activity in human erythrocytes. Changes in the K+ permeability were monitored by flux measurements and single-channel recordings. The enzyme activity was detected by measuring reduction of ferricyanide. Pb2+, Atebrin and menadione had parallel effects on the channel protein and the enzyme. In contrast, propranolol stimulates K+ permeability, but is without effect on enzyme activity. The results demonstrate that the K+ channel and the enzyme are distinct membrane proteins but that the enzyme activity may influence channel gating.
Fehlau
R
R
Institut für Pharmakologie und Toxikologie, Universität Marburg, F.R.G.
Grygorczyk
R
R
Fuhrmann
G F
GF
Schwarz
W
W
D002118:Calcium / Q000494:pharmacology*; D004910:Erythrocyte Membrane / Q000378:metabolism*; D006801:Humans; D007854:Lead / Q000494:pharmacology*; D008565:Membrane Proteins / Q000097:blood; D009247:NADH, NADPH Oxidoreductases / Q000037:antagonists & inhibitors / Q000097:blood; D011188:Potassium / Q000097:blood; D015221:Potassium Channels / Q000187:drug effects / Q000378:metabolism*; D011796:Quinacrine / Q000494:pharmacology; D014812:Vitamin K / Q000494:pharmacology
D008565:Membrane Proteins; D015221:Potassium Channels; D014812:Vitamin K; D007854:Lead; D009247:NADH, NADPH Oxidoreductases; C014227:ferricyanide reductase; D011796:Quinacrine; D011188:Potassium; D002118:Calcium