ISSN:
1432-2013
Schlagwort(e):
Enterocytes
;
Potassium
;
Ca2+-activated K+ channels
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Medizin
Notizen:
Abstract The transport of potassium has been studied in epithelial cells isolated from chicken small intestine using86Rb as a tracer for K+. (i) The uptake studies revealed that about 60% of the total K+ net flux is inhibited by ouabain and therefore mediated by the Na+−K+-ATPase. About 20% of the ouabain-insensitive K+ net influx was inhibited by furosemide, bumetanide and by either Na+ or Cl− removal from the incubation solution, suggesting that a Na+/Cl−/K+ cotransport system might be present in chicken enterocytes. (ii) The efflux of K+ was measured from cells preloaded with86Rb. K+ efflux was inhibited by Ba2+, quinine and verapamil; it was stimulated by A23187, and it was unaffected by 3,4-diaminopyridine. Apamin, that has no effect on basal rates of K+ efflux, abolished the effect of A23187. These findings suggest that K+ efflux appears to occur through Ca2+-activated K+ channels.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF01907562
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