Choline uptake across the ventricular membrane of neonate rat choroid plexus.
Choline uptake across the ventricular membrane of neonate rat choroid plexus.
复制标题
新生大鼠脉络丛心室膜胆碱的摄取。
DOI：
10.1152/ajpcell.1999.276.6.c1288
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
Renfro,JL
中科院分区：
文献类型：
--
作者：
Villalobos,AR;Parmelee,JT;Renfro,JL
[3 H]胆碱的摄取从脑脊液（CSF）侧的新生大鼠脉络丛的脉络膜上皮生长在固体支持物的原代培养的特点。细胞与培养基的浓度比在1分钟时为10.5，在30分钟时高达70。几种有机阳离子（例如，hemicholinium-3和N1-methylnicotinamide）抑制摄取。减少或去除外部Na+或添加5 mM LiCl对摄取没有影响。然而，将外部K+浓度从3 mM增加到30 mM使心室膜电位去极化（−70 mV到−15 mV），并将摄取减少到对照组的45%。用1 mM哇巴因或2 mM BaCl 2处理可使摄取减少45%，细胞内酸化可使摄取减少至对照组的约90%。这些数据表明，从CSF中摄取胆碱跨新生儿脉络膜上皮细胞的心室膜是不直接耦合到Na+内流，但质膜电位是敏感的。
The uptake of [3H]choline from the cerebrospinal fluid (CSF) side of the rat neonatal choroid plexus was characterized in primary cultures of the choroidal epithelium grown on solid supports. Cell-to-medium concentration ratios were ∼5 at 1 min and as high as 70 at 30 min. Apical choline uptake was facilitated; theKmwas ∼50 μM. Several organic cations (e.g., hemicholinium-3 andN1-methylnicotinamide) inhibited uptake. The reduction or removal of external Na+or the addition of 5 mM LiCl had no effect on uptake. However, increasing external K+concentration from 3 to 30 mM depolarized ventricular membrane potential (−70 to −15 mV) and reduced uptake to 45% of that for the control. Treatment with 1 mM ouabain or 2 mM BaCl2reduced uptake 45%, and intracellular acidification reduced uptake to ∼90% of that for controls. These data indicate that the uptake of choline from CSF across the ventricular membrane of the neonatal choroidal epithelium is not directly coupled to Na+influx but is sensitive to plasma membrane electrical potential.