Selective activation of exocytosis by low concentrations of ACh in rat pancreatic acinar cells.
Selective activation of exocytosis by low concentrations of ACh in rat pancreatic acinar cells.
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大鼠胰腺腺泡细胞中低浓度 ACh 选择性激活胞吐作用。
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
Y. Maruyama
中科院分区：
文献类型：
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作者：
Y. Maruyama
1.我们监测了毒蕈碱乙酰胆碱刺激单个大鼠胰腺腺泡细胞引起的膜电容（Δ C）和电导（Δ G）的变化。2.乙酰胆碱（ACh，500 nM）诱导δ C和δ G同时增加。相比之下，低浓度（50 nM）的ACh只诱导δ C增加，而没有δ G。这些反应被肝素的内部灌注所消除。这表明肌醇1，4，5-三磷酸介导的内部Ca 2+动员可以同时激活胞吐和离子通道，也可以仅启动胞吐。相比之下，低浓度的A23187选择性地激活离子通道，但高浓度同时激活胞吐和离子通道。3.δ C和δ G的这些选择性反应模式取决于激动剂的选择和内部EGTA浓度。从这一点，我们假设两种解释的选择性行动的毒蕈碱乙酰胆碱刺激胞吐。首先，高[Ca 2 +]i的区域，空间上接近分泌颗粒，激活胞吐作用。第二，一个未知的信号传导因子敏感的Ca 2+亲和力的胞吐器。
1. We have monitored changes in membrane capacitance (delta C) and conductance (delta G) induced by muscarinic acetylcholine stimulation in single rat pancreatic acinar cells. 2. Acetylcholine (ACh, 500 nM) induced simultaneous increases of delta C and delta G. In contrast, a low concentration (50 nM) of ACh exclusively induced delta C increases without delta G. These responses were abolished by the internal perfusion of heparin. This indicates that inositol 1,4,5‐trisphosphate‐mediated internal Ca2+ mobilization either simultaneously activates exocytosis and ion channels or exclusively initiates exocytosis. In comparison, a low concentration of A23187 selectively activated ion channels but a high concentration activated exocytosis and ion channels simultaneously. 3. These selective response patterns of delta C and delta G depend on the choice of agonist and the internal EGTA concentration. From this, we postulated two explanations for the selective action of muscarinic ACh stimulation on exocytosis. First, an area of high [Ca2+]i, spatially close to secretory granules, activates exocytosis. Second, an as yet unknown signalling factor sensitizes the Ca2+ affinity of the exocytotic apparatus.
胰腺腺泡细胞 Ca2 波触发区中 3 型肌醇 1,4,5-三磷酸受体的定位。
DOI：
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发表时间：
1994
期刊：
The Journal of biological chemistry
影响因子：
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作者：
Nathanson,MH;Fallon,MB;Padfield,PJ;Maranto,AR
通讯作者：
Maranto,AR
肝素对肌醇 1,4,5-三磷酸激活的钙释放具有竞争性、可逆性和强效拮抗作用。
DOI：
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发表时间：
1988
期刊：
The Journal of biological chemistry
影响因子：
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作者：
Ghosh,TK;Eis,PS;Mullaney,JM;Ebert,CL;Gill,DL
通讯作者：
Gill,DL