Evidence for a sodium/calcium exchanger and voltage-dependent calcium channels in adipocytes.
Evidence for a sodium/calcium exchanger and voltage-dependent calcium channels in adipocytes.
复制标题
脂肪细胞中钠/钙交换器和电压依赖性钙通道的证据。
DOI：
10.1016/0014-5793(89)81169-x
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发表时间：
1989
期刊：
影响因子：
3.5
通讯作者：
Snowdowne,KW
中科院分区：
文献类型：
--
作者：
Pershadsingh,HA;Lee,LY;Snowdowne,KW
这些研究的目的是确定和表征钙离子转运系统，可能是潜在的重要性，在行动中的钙离子动员激素在脂肪细胞。用Ca ~（2+）敏感的发光蛋白水母发光蛋白（aequorin），[Ca ~（2+）] i估计为0.15 μM，假设胞内[Mg ~（2+）]为1 mM.用胆碱~+取代Na ~+，引起[Ca ~（2+）] i的瞬时增加，与胞外[Na ~+]呈负相关，与介导的Na ~+-Ca ~（2+）交换系统的操作一致.化学计量比为3 Na+：Ca 2+。细胞外K+升高引起[Ca 2 +] i增加，Ca 2+通道拮抗剂地尔硫卓通过省略细胞外Ca 2+或用Sr 2+替代Ca 2+来阻断[Ca 2 +] i。这些发现表明脂肪细胞中存在Na+-Ca 2+交换器和电压敏感性Ca 2+通道。
The objective of these studies is to identify and characterize Ca2+-transport systems that may be of potential importance in the action of Ca2+-mobilizing hormones in the adipocyte. Using the Ca2+-sensitive photoprotein, aequorin, [Ca2+]iwas estimated to be 0.15 μM, assuming an intracellular [Mg2+] of 1 mM. Substitution of Na+with choline+caused a transient increase in [Ca2+]iwhich was inversely related to extracellular [Na+], consistent with operation of a mediated Na+-Ca2+exchange system. The stoichiometry was 3Na+:Ca2+. Elevation of extracellular K+caused an increase in [Ca2+]ithat was blocked by the Ca2+channel antagonist, diltiazem, by omitting extracellular Ca2+, or by substituting Sr2+for Ca2+. These findings indicate the presence of an Na+-Ca2+exchanger and voltage-sensitive Ca2+channels in adipocytes.