Ultramicroelectrode Detection of Adrenaline Releases by Chromaffin Cells: Physical-Chemistry Governs the Dynamics of Exocytosis
نویسندگان
چکیده
Exocytosis of adrenaline by chromaffin cells occurs trough a process involving docking and then fusion of a secretory vesicle to the cytoplasmic membrane of the cell. Fusion proceeds in two main stages. The first one leads to the creation of a stable fusion pore (see figure) between the two membranes and which gives a constant release flux of neurotransmitter (pore release stage). After a few milliseconds, this initial stage proceeds through a sudden enlargement of the pore up to the complete incorporation of the vesicle membrane into that of the cell (full fusion stage) and total exposure of the initial matrix vesicle core to the extracellular medium where the ultramicroelectrode is located. [2]
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