The effect of harmaline on unidirectional potassium fluxes and ouabain binding in renal cell cultures.
Harmaline inhibits K+ influx into primary cell cultures of ground squirrel kidneys to a greater extent than either ouabain or furosemide. A concentration of 200 microM harmaline was required to inhibit half of the total K+ influx; this effect was also seen at low temperature (5 degrees C), and in another species (hamster). Although kinetic analysis of K+ influx indicates that harmaline does not compete with extracellular K+, harmaline did reduce the binding of [3H]ouabain to the cells. K+ efflux was also reduced. Therefore, harmaline may inhibit the furosemide-sensitive Na+/K+ cotransport system as well as the ouabain-sensitive Na+/K+ pump.
D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002478:Cells, Cultured; D006224:Cricetinae; D006246:Harmaline / Q000494:pharmacology*; D007672:Kidney Cortex / Q000378:metabolism*; D007700:Kinetics; D008647:Mesocricetus; D010042:Ouabain / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism*; D011955:Receptors, Drug / Q000187:drug effects / Q000378:metabolism*; D012589:Sciuridae; D000254:Sodium-Potassium-Exchanging ATPase; D013045:Species Specificity
D000470:Alkaloids; D011955:Receptors, Drug; C028996:cardiac glycoside receptors; D010042:Ouabain; D006246:Harmaline; D000254:Sodium-Potassium-Exchanging ATPase; D011188:Potassium