Active sodium and chloride transport across the rabbit blastocoele wall.
Active sodium and chloride transport across the rabbit blastocoele wall.
复制标题
活性钠和氯通过兔囊腔壁运输。
作者：
M. H. Cross
通过测量“Na”和“Cl”在短路制剂中的单向通量，研究了6天家兔囊胚的离子转运过程。当含有25 mM HCO的Eagle培养基（20%牛血清）浸泡在胚腔两侧时，跨壁电位差降至零，从外部洗液到胚腔的净Na通量（0.58±0.15 μ M/cm ' /h）和净Cl通量（0.59±0.14 μ M/cm ' /h）。净Na和CI通量均大于短路电流的3倍，仅占短路电流的5%。将外部洗浴介质改为不含HCO的溶液，大大降低了电位差和短路电流，而从外部溶液中去除Na和Cl离子则没有效果。由此可见，Na和Cl被主动转运到兔囊胚中，而在不含HCO的溶液中，短路电流中存在一种方向适当的未知成分，大大减少了短路电流，这表明兔囊胚也在主动转运HCO。
Ion transport processes of the 6-day rabbit blastocyst were examined in vitro by measuring unidirectional fluxes of “Na and “Cl across the short-circuited preparation. When Eagle’s medium (20% calf serum) containing 25 mM HCO, bathed both sides of the blastocoele and the transmural potential difference was reduced to zero, there was a net Na flux (0.58 ± 0.15 �M/cm’/h) and a net Cl flux (0.59 ± 0.14 �M/cm’/h) from the outside bathing solution to the blastocoele. Net Na and CI fluxes were both three times larger than the short-circuit current and accounted for only 5% of the short-circuit current. Changing the outside bathing medium to a HCO,-free solution greatly reduced the potential difference and short-circuit current, whereas removal of Na and Cl ions from the outside solution had no effect. It is concluded that Na and Cl are actively transported into the rabbit blastocoele, and the presence of an appropriately directed unidentified component of short-circuit current, which is greatly reduced in HCO,-free solutions, suggests that the rabbit blastocyst also actively transports HCO,.