Distribution of Ca2+ extrusion sites on the mouse pancreatic acinar cell surface
Distribution of Ca2+ extrusion sites on the mouse pancreatic acinar cell surface
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DOI：
10.1016/s0143-4160(97)90084-1
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发表时间：
1997-07-01
期刊：
影响因子：
4
通讯作者：
Tepikin, AV
中科院分区：
文献类型：
--
作者：
Belan, P;Gerasimenko, O;Tepikin, AV
本文研究了小鼠胰腺腺泡细胞内游离钙浓度（[Ca ~（2+）]（i））升高过程中Ca ~（2+）挤出位点的定位。在激动剂刺激的钙升高期间以及当细胞内钙从“笼状化合物”释放时，尽管[Ca 2 +]（i）的空间模式不同、Ca 2+的来源不同以及激动剂的存在或不存在，但Ca 2+主要从细胞的顶端分泌极挤出。这最可能是由于分泌颗粒区域中相对高密度的钙泵，尽管这可以解释为这部分细胞中的钙泵具有与基底膜中的钙泵不同的特性。在顶端分泌极中的Ca 2+挤出的强度是这样的，即在激动剂刺激期间可以发生腺泡内腔中游离钙浓度的实质性（几毫摩尔/升）变化。
The localizations of Ca2+ extrusion sites in mouse pancreatic acinar cells during elevation of the intracellular free calcium concentration ([Ca2+](i)) have been studied. During an agonist stimulated calcium elevation as well as when intracellular calcium is released from a 'caged compound', Ca2+ is primarily extruded from the apical secretory pole of the cells in spite of different spatial patterns of [Ca2+](i), different sources of Ca2+, and the presence or absence of agonist, This is most likely due to a relatively high density of calcium pumps in the secretory granule region, although it could be explained by calcium pumps in this part of the cell having different characteristics from those in the basal membrane. The intensity of Ca2+ extrusion in the apical secretory pole is such that substantial (several millimoles per litre) changes of the free calcium concentration in the lumen of the acinus can occur during agonist stimulation.