Role of chloride transport in the development of the rat blastocyst.
Preimplantation mammalian development culminates in the generation of a fluid-filled cavity, the blastocoel, which requires the vectorial transport of ions across the trophectoderm, followed by the movement of water. Experiments were carried out to establish the role of Cl- transport in blastocoel formation in the rat. These included investigations of the effect of Cl- substitution and the Cl- transport inhibitors 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid, furosemide, and anthracene-9-carboxylic acid, on the development of morulae into blastocysts in culture, and on the rate at which blastocoel fluid is accumulated. In addition, a novel technique was developed in which the Cl(-)-sensitive fluorescent dye 6-methoxy-N-(3-sulfopropyl) quinolium (SPQ) was loaded into the blastocoel cavity, in order to characterize the pathways of transtrophectodermal Cl- transport. We established that 1) blastocoel formation in the rat requires the external presence of Cl- ions; 2) transport across the trophectoderm appears to be via a transcellular pathway, since rates of blastocyst development, fluid accumulation, and SPQ-monitored Cl- efflux are all reduced in the presence of Cl- transport inhibitors; and 3) Cl- transport occurs via Cl-/HCO3- exchange.
Department of Biology, University of York, Heslington, United Kingdom.
D R
DR
Brison
H J
HJ
Leese
D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D000873:Anthracenes / Q000494:pharmacology; D001755:Blastocyst / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002712:Chlorides / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D005314:Embryonic and Fetal Development / Q000187:drug effects / Q000502:physiology*; D005260:Female; D005456:Fluorescent Dyes; D005665:Furosemide / Q000494:pharmacology; D066298:In Vitro Techniques; D017136:Ion Transport / Q000187:drug effects; D011806:Quinolinium Compounds; D051381:Rats; D017208:Rats, Wistar
D000873:Anthracenes; D002712:Chlorides; D005456:Fluorescent Dyes; D011806:Quinolinium Compounds; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; C010030:9-anthroic acid; D005665:Furosemide; C052335:6-methoxy-N-(3-sulfopropyl)quinolinium; D000242:Cyclic AMP; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D002118:Calcium