Phospholipid mediated plasticity in exocytosis observed in PC12 cells
Phospholipid mediated plasticity in exocytosis observed in PC12 cells
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DOI：
10.1016/j.brainres.2007.03.012
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发表时间：
2007-06-02
期刊：
影响因子：
2.9
通讯作者：
Ewing, Andrew G.
中科院分区：
文献类型：
--
作者：
Uchiyama, Yoshiko;Maxson, Marc M.;Ewing, Andrew G.
膜组成用于识别细胞内区室，信号细胞死亡，以及改变细胞的电和物理性质。在这里，我们使用电流法显示，补充磷脂磷脂酰胆碱（PC），磷脂酰乙醇胺（PE），鞘磷脂（SM）和磷脂酰丝氨酸（PS）可以改变胞吐作用的几个方面。电流峰形状的变化来自个人exocytosing囊泡显示，PC减缓驱逐的神经递质，而PE加速驱逐的神经递质。电流测量数据显示，PC处理的细胞每次释放的儿茶酚胺量减少，而电子显微镜显示这些细胞中的囊泡比对照组大50%，从而提供了囊泡浓度发生药理学变化的证据。SM的加入似乎会影响融合孔扩张的速率，由较慢的峰值上升时间表示，但不影响衰减时间或量子尺寸。PS的加入导致高K+去极化引起的事件数量增加1.7倍。PS处理的细胞的电子显微镜照片表明，增加囊泡募集的基础增强分泌。我们没有观察到磷脂酰肌醇（PI）治疗的任何影响。总之，这些数据表明，膜组成的差异影响胞吐作用，并可能参与细胞功能的机制，通过胞吐作用控制通信的动力学。(C)2007 Elsevier B.V.保留所有权利。
Membrane composition serves to identify intracellular compartments, signal cell death, as well as to alter a cell's electrical and physical properties. Here we use amperometry to show that supplementation with the phospholipids phosphatidylcholine (PC), phosphatidylethanolamine (PE), sphingomyelin (SM), and phosphatidylserine (PS) can alter several aspects of exocytosis. Changes in the amperometric peak shape derived from individual exocytosing vesicles reveal that PC slows expulsion of neurotransmitter while PE accelerates expulsion of neurotransmitter. Amperometry data reveal a reduced amount of catecholarnine released per event from PC-treated cells while electron micrographs indicate the vesicles in these cells are 50%largerthan controls, thus providing evidence of pharmacological changes in vesicle concentration. Addition of SM appears to affect the rate of fusion pore expansion, indicated by slowerpeak rise times, but does not affect decay times or quantal size. Addition of PS results in a 1.7-fold increase in the number of events elicited by high-K+ depolarization. Electron micrographs of PS-treated cells suggest that increased vesicle recruitment underlies enhanced secretion. We did not observe any effect of phosphatidylinositol (PI) treatment. Together these data suggest that differences in membrane composition affect exocytosis and might be involved in mechanisms of cell function controlling the dynamics of communication via exocytosis. (C) 2007 Elsevier B.V. All rights reserved.