Altered erythrocyte cation permeability in familial pseudohyperkalaemia.
1. Erythrocyte cation transport pathways have been investigated in a family with pseudohyperkalaemia. 2. Ouabain- and bumetanide-resistant Na+ and K+ effluxes in three pseudohyperkalaemic patients were not different from those of control subjects when assessed at 37 degrees C. 3. When the temperature was decreased to 20 degrees C and 9 degrees C, K+ passive permeability markedly increased and Na+ permeability remained unchanged in these patients. In contrast, in control subjects a reduction in temperature caused a marked reduction in Na+ and K+ passive permeability. 4. These findings could account for the marked increase in plasma K+ concentration observed at subphysiological temperatures. 5. The Na+-K+ co-transport pathway was reduced in all members of the family, but the Na+-K+ pump was reduced in only two of them. These alterations were independent from the pseudohyperkalaemic state.
Laboratoire de Physiologie Cellulaire, Collège de France Paris, France.
G
G
Dagher
M C
MC
Vantyghem
B
B
Doise
G
G
Lallau
A
A
Racadot
J
J
Lefebvre
D000368:Aged; D002463:Cell Membrane Permeability; D004910:Erythrocyte Membrane / Q000378:metabolism*; D005190:Family; D005260:Female; D006801:Humans; D006947:Hyperkalemia / Q000097:blood* / Q000235:genetics; D008297:Male; D011188:Potassium / Q000097:blood*; D012964:Sodium / Q000097:blood*
D012964:Sodium; D011188:Potassium