Potassium influx in human neonatal red blood cells. Partition into its major components.
The potassium influx in human neonatal red blood cells (nRBC) shows an approximately 25% lower value compared to the total potassium influx in adult red blood cells (aRBC). The ouabain-sensitive potassium influx component represents approximately 70-75% of the total potassium influx for both types of cells but with an absolute value significantly lower in nRBC. In nRBC, the half maximum inhibitory effect for ouabain was obtained at a 10(-9) M concentration. The ouabain-insensitive nRBC potassium influx fractions showed two components: (i) a bumetanide-sensitive component, significantly lower than that of aRBC, (ii) a ouabain-bumetanide-insensitive (leak) component with a similar value in both cell types. The sum of the ouabain-sensitive and furosemide-sensitive components amounted in nRBC to a greater value than the total potassium influx. This behaviour could be interpreted as a superposition of the action of the inhibitors on the components affected.
Cátedra de Fisiología Humana, Facultad de Ciencias Médicas, Universidad Nacional de Rosario, Argentina.
R E
RE
Serrani
G
G
Venera
I A
IA
Gioia
J L
JL
Corchs
D000328:Adult; D001692:Biological Transport / Q000187:drug effects; D002034:Bumetanide / Q000494:pharmacology; D004912:Erythrocytes / Q000187:drug effects / Q000378:metabolism*; D005312:Fetal Blood / Q000378:metabolism*; D005665:Furosemide / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism*
D002034:Bumetanide; D010042:Ouabain; D005665:Furosemide; D011188:Potassium