title: Frusemide-sensitive sodium and potassium transport by human leucocytes.
abstract: Frusemide-sensitive sodium and potassium transport by normal human leucocytes has been studied in vitro by both isotopic and net flux techniques. In physiological media the leucocyte exhibits a frusemide-sensitive influx of sodium and potassium of equal magnitude compatible with a 1:1 co-transport system. Cells exposed to zero external sodium and potassium (osmolality maintained with choline) demonstrated a frusemide-sensitive sodium and potassium efflux. Frusemide-sensitive potassium influx was dependent on the presence of external sodium but frusemide-sensitive sodium influx persisted unchanged in the absence of external potassium. Frusemide-sensitive potassium influx was dependent on external chloride but frusemide-sensitive sodium influx was chloride-independent. These last two observations make it likely that the frusemide-sensitive pathway is capable of operating in modes other than sodium-potassium co-transport.
mesh_terms: D001693:Biological Transport, Active / Q000187:drug effects; D002712:Chlorides / Q000097:blood; D005665:Furosemide / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D007962:Leukocytes / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000097:blood*; D012964:Sodium / Q000097:blood*
chemical_list: D002712:Chlorides; D005665:Furosemide; D012964:Sodium; D011188:Potassium