The Na+/K+ co-transport system in erythrocytes from pregnant patients.
In erythrocytes, the extrusion of a cellular sodium level load is accomplished by the Ouabain--sensitive Na+/K+ pump and by the furosemide-sensitive Na+/K(+)--cotransport, which operates against the passive sodium permeability. An abnormal low rate of net sodium extrusion by the Na+/K+ cotransport was observed in pre-eclamptic patients. At the molecular level the cotransport abnormality seems to be the consequence of an apparent diminished affinity for intracellular Na+. Normal pregnancy is characterized by a strong increase of Na+/K+ cotransport efflux. No difference could be detected between the passive sodium permeability of erythrocytes from normotensive pregnant patients and from normotensive non-pregnant controls. Pre-eclampsia seems to be associated with a low passive sodium and potassium permeability. The abnormalities of cotransport and red cell deformability in patients with pre-eclampsia might be interpreted as an early sign of impaired microcirculation and increased vascular reactivity.
Heilmann
L
L
Abteilung für Frauenheilkunde und Geburtshilfe, Stadtkrankenhaus, Rüsselsheim, Germany.
von Tempelhoff
G F
GF
Ulrich
S
S
D000293:Adolescent; D000328:Adult; D001794:Blood Pressure; D016022:Case-Control Studies; D002463:Cell Membrane Permeability; D004058:Diffusion; D004907:Erythrocyte Deformability; D004912:Erythrocytes / Q000502:physiology*; D005260:Female; D005665:Furosemide / Q000494:pharmacology; D006801:Humans; D017136:Ion Transport / Q000187:drug effects / Q000502:physiology*; D008833:Microcirculation; D010042:Ouabain / Q000494:pharmacology; D011225:Pre-Eclampsia / Q000097:blood* / Q000503:physiopathology; D011247:Pregnancy; D012044:Regression Analysis; D000254:Sodium-Potassium-Exchanging ATPase / Q000187:drug effects / Q000502:physiology*; D014655:Vascular Resistance
D010042:Ouabain; D005665:Furosemide; D000254:Sodium-Potassium-Exchanging ATPase