TY - JOUR
T1 - The Effects of Vesicular Volume on Secretion through the Fusion Pore in Exocytotic Release from PC12 Cells
AU - Sombers, L. A.
AU - Hanchar, H. J.
AU - Colliver, T. L.
AU - Wittenberg, N.
AU - Cans, A.
AU - Arbault, S.
AU - Amatore, C.
AU - Ewing, Andrew G.
PY - 2004/1/14
Y1 - 2004/1/14
N2 - Many spikes in amperometric records of exocytosis events initially exhibit a prespike feature, or foot, which represents a steady-state flux of neurotransmitter through a stable fusion pore spanning both the vesicle and plasma membranes and connecting the vesicle lumen to the extracellular fluid. Here, we present the first evidence indicating that vesicular volume before secretion is strongly correlated with the characteristics of amperometric foot events. L-3,4-Dihydroxyphenylalanine and reserpine have been used to increase and decrease, respectively, the volume of single pheochromocytoma cell vesicles. Amperometry and transmission electron microscopy have been used to determine that as vesicle size is decreased the frequency with which foot events are observed increases, the amount and duration of neurotransmitter released in the foot portion of the event decreases, and vesicles release a greater percentage of their total contents in the foot portion of the event. This previously unidentified correlation provides new insight into how vesicle volume can modulate the activity of the exocytotic fusion pore.
AB - Many spikes in amperometric records of exocytosis events initially exhibit a prespike feature, or foot, which represents a steady-state flux of neurotransmitter through a stable fusion pore spanning both the vesicle and plasma membranes and connecting the vesicle lumen to the extracellular fluid. Here, we present the first evidence indicating that vesicular volume before secretion is strongly correlated with the characteristics of amperometric foot events. L-3,4-Dihydroxyphenylalanine and reserpine have been used to increase and decrease, respectively, the volume of single pheochromocytoma cell vesicles. Amperometry and transmission electron microscopy have been used to determine that as vesicle size is decreased the frequency with which foot events are observed increases, the amount and duration of neurotransmitter released in the foot portion of the event decreases, and vesicles release a greater percentage of their total contents in the foot portion of the event. This previously unidentified correlation provides new insight into how vesicle volume can modulate the activity of the exocytotic fusion pore.
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U2 - 10.1523/JNEUROSCI.1119-03.2004
DO - 10.1523/JNEUROSCI.1119-03.2004
M3 - Article
C2 - 14724228
AN - SCOPUS:1642540051
SN - 0270-6474
VL - 24
SP - 303
EP - 309
JO - Journal of Neuroscience
JF - Journal of Neuroscience
IS - 2
ER -