Membrane potential difference and intracellular cation concentrations in human placental trophoblast cells in culture.

摘要: 1. The electrochemical gradients for Na+ and K+ were assessed in a cell culture model of trophoblast differentiation. 2. Membrane potential difference (Em), intracellular water contents measured choriocarcinoma cells (JAr line; 96% which are undifferentiated cells) mononucleate multinucleate (differentiated) cytotrophoblast isolated from the human placenta at term. 3. There was significant fall Em -57 mV JAr cells, to -48 -40 mono-and respectively. Treatment with ouabain (1 mM 15 min) depolarized membrane by but did not affect potential. 4. Intracellular concentration similar JAr, mono- higher compared cells. 5. Ouabain treatment (3 caused small increase (4.5%) lowered (approximately 30%) increased 125%) all studied. 6. equilibrium (EK) more negative than between EK smaller (-25 mV) (-33 -43 mV, respectively). 7. (ENa) positive ENa 122, 100 8. These results suggest that gradient is affected stage In contrast,