CAPACITANCE MEASUREMENTS REVEAL STEPWISE FUSION EVENTS IN DEGRANULATING MAST-CELLS
CAPACITANCE MEASUREMENTS REVEAL STEPWISE FUSION EVENTS IN DEGRANULATING MAST-CELLS
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DOI：
10.1038/312453a0
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发表时间：
1984-01-01
期刊：
影响因子：
64.8
通讯作者：
GOMPERTS, BD
中科院分区：
文献类型：
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作者：
FERNANDEZ, JM;NEHER, E;GOMPERTS, BD
肥大细胞在刺激下会发生广泛而剧烈的形态学变化。在这里，我们描述的动态融合的分泌颗粒在个别肥大细胞在胞吐作用。细胞膜电容（与细胞表面积成比例）使用全细胞贴片移液管技术2，3测量，其中细胞内空间用用于填充贴片移液管的溶液透析。我们的结果表明，如果GTP类似物、GTP-γ-S和Mg-ATP存在于移液器填充溶液中，则脱粒自发且可重复发生。与以前的报告4 -8相反，在这些条件下，脱颗粒不需要Ca 2+（和/或Ca 2+缓冲液）。虽然生电Ca 2+进入之前或期间脱粒和膜电导保持低，电容，并暗示脱粒细胞的膜面积，增加sigmoidally和逐步。我们的结论是，电容的逐步增加是由于融合的个别分泌颗粒与质膜，鸟嘌呤核苷酸调节蛋白参与控制这一过程。
Mast cells undergo an extensive and violent morphological transformation on stimulation1. Here we describe the dynamics of fusion of the secretory granules in individual mast cells during exocytosis. The cell membrane capacitance (proportional to the cell surface area) was measured using the whole-cell patch-pipette technique2,3, in which the intracellular space is dialysed with the solutions used to fill the patch pipette. Our results show that degranulation occurs spontaneously and reproducibly if the GTP analogue, GTP-γ-S, and Mg-ATP are present in the pipette filling solution. Contrary to previous reports4–8, in these conditions Ca2+(and/or Ca2+buffers) is not required for degranulation. Although electrogenic Ca2+entry was not detected before or during degranulation and membrane conductance remained low, the capacitance, and by implication the area of the membrane of degranulating cells, increased sigmoidally and stepwise. We conclude that stepwise increases of capacitance are due to the fusion of individual secretory granules with the plasma membrane, and that guanine nucleotide regulatory proteins are involved in the control of this process.