Sodium and chloride co-transport by preimplantation rabbit blastocysts.
Influxes of Na+ and Cl- across the trophectodermal epithelium of 6 day post coitum (p.c.) rabbit blastocysts are partially interrelated. This relationship was investigated under conditions in which either the external [Na+] or [Cl-] concentration was varied. Our results indicate that an ouabain-insensitive, furosemide-sensitive, Na+:Cl- co-transport system exists in the 6 and 6.5 day p.c. rabbit embryo, but not in the 5 day p.c. blastocyst. There was no dependence of NaCl uptake on the presence of K+ in the bathing medium. No evidence of Na+/H+ or Cl-/HCO3- exchange systems in the rabbit blastocyst was found. The effects of furosemide, exogenous cyclic AMP, and various exogenous prostaglandins on Na+ and Cl- movements were studied. Cyclic AMP and/or prostaglandin E1 may regulate the operation of this Na+:Cl- co-transport system.
D000818:Animals; D001693:Biological Transport, Active; D001755:Blastocyst / Q000378:metabolism*; D003994:Bucladesine / Q000494:pharmacology; D002478:Cells, Cultured; D002712:Chlorides / Q000378:metabolism*; D047108:Embryonic Development; D005260:Female; D005665:Furosemide / Q000494:pharmacology; D010042:Ouabain / Q000494:pharmacology; D010693:Phloretin / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D011247:Pregnancy; D011453:Prostaglandins / Q000494:pharmacology; D011817:Rabbits; D012964:Sodium / Q000378:metabolism*; D013997:Time Factors
D002712:Chlorides; D011453:Prostaglandins; D010042:Ouabain; D003994:Bucladesine; D005665:Furosemide; D012964:Sodium; D011188:Potassium; D010693:Phloretin