Ouabain-sensitive fluid accumulation and ion transport by rabbit blastocysts.
1. By incubating 6-day post-coitum (p.c.) blastocysts in medium supplemented with either 20 mM-sucrose or 10 mM-KCl it was possible to show that the trophectoderm of the blastocyst prevents the concentration of K in the blastocoele fluid rising to external concentrations. 2. The concentrations of K in the blastocoele fluid are maintained predominantly by leakage of K from the trophoblast cells into the blastocoele and by ouabain-sensitive transport of K into the trophoblast cells from the blastocoele fluid. 3. Exposure of blastocysts to ouabain on the juxtacoelic, but not abcoelic, surface of the trophectoderm may inhibit blastocoele fluid accumulation.
D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D001755:Blastocyst / Q000187:drug effects / Q000378:metabolism*; D004577:Electron Probe Microanalysis; D066298:In Vitro Techniques; D010042:Ouabain / Q000494:pharmacology*; D011188:Potassium / Q000378:metabolism / Q000494:pharmacology; D011817:Rabbits; D012964:Sodium / Q000378:metabolism; D014327:Trophoblasts / Q000378:metabolism
D010042:Ouabain; D012964:Sodium; D011188:Potassium