Fetomaternal potassium relations in the rat on the twentieth day of gestation. II. Effects of maternal hypokalemia.
Time-corrected measurements of transplacental and transamniotic electrical potentials were made in potassium-deficient rats on the 20th day of gestation. These averaged 6.4 mV and 2.0 mV, respectively, in the deficient group as compared with 14.3 and 18.4, respectively, in the controls. The measured maternal potassium concentrations were 2.8 mEq/liter in the K+-restricted animals and 4.8 mEq/liter in the controls. These figures were substituted into the Nernst equation in order to predict fetal concentrations in plasma. Similar predictions were made for amniotic fluid assuming equilibrium with fetal plasma. Predicted concentrations in fetal plasma were 2.3 mEq/liter in the deficient animals and 2.8 mEq/liter in the controls. By contrast, observed time-corrected potassium concentrations in fetal plasma were 4.0 mEq/liter in deficient animals and 2.9 mEq/liter in controls. Amniotic fluid values were predicted to be 4.7 mEq/liter in deficient and 2.5 mEq/liter in control animals. These values were compared with the observed averages in amniotic fluid of 4.7 and 4.6 mEq/liter in the deficient and control groups, respectively.
D000653:Amniotic Fluid / Q000032:analysis; D000818:Animals; D005260:Female; D005312:Fetal Blood / Q000032:analysis*; D007008:Hypokalemia / Q000097:blood* / Q000378:metabolism; D011188:Potassium / Q000032:analysis / Q000097:blood*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood* / Q000378:metabolism; D051381:Rats
D011188:Potassium