TY - JOUR
T1 - Fast endocytosis is inhibited by GABA-mediated chloride influx at a presynaptic terminal
AU - Hull, Court
AU - Von Gersdorff, Henrique
N1 - Funding Information:
We thank Steven Yazulla (SUNY at Stony Brook, NY) for generously donating the goldfish bipolar cell electron micrograph. We thank Craig Jahr, Gary Matthews, Mary J. Palmer, and Jozsef Vigh for discussions. This work was supported by a grant from the NEI (H.v.G.) and an NRSA predoctoral fellowship (C.H.).
PY - 2004/10/28
Y1 - 2004/10/28
N2 - Although multiple kinetic components of synaptic vesicle endocytosis have been identified, it has remained unclear whether neurons can differentially modulate these components. Using membrane capacitance measurements from isolated goldfish bipolar cell terminals, we found that the kinetics of endocytosis in retinal slices (single exponential decay; τ > 10 s) were significantly slower than those in acutely dissociated terminals (double exponential decay; τfast ≅ 1-2 s; τslow > 10 s). Surprisingly, GABAA and/or GABAC receptor antagonists restored the fast component of endocytosis to terminals in retinal slices. Blocking GABAergic feedback from reciprocal synapses or removing external Cl- ions also allowed for fast endocytosis. Elevating internal Cl- via the patch pipette invariably slowed endocytosis, even in terminals dialyzed with increased Ca2+ buffer. These results suggest a new role for GABA and Cl- ions in blocking the trigger for fast endocytosis at this ribbon-type synapse.
AB - Although multiple kinetic components of synaptic vesicle endocytosis have been identified, it has remained unclear whether neurons can differentially modulate these components. Using membrane capacitance measurements from isolated goldfish bipolar cell terminals, we found that the kinetics of endocytosis in retinal slices (single exponential decay; τ > 10 s) were significantly slower than those in acutely dissociated terminals (double exponential decay; τfast ≅ 1-2 s; τslow > 10 s). Surprisingly, GABAA and/or GABAC receptor antagonists restored the fast component of endocytosis to terminals in retinal slices. Blocking GABAergic feedback from reciprocal synapses or removing external Cl- ions also allowed for fast endocytosis. Elevating internal Cl- via the patch pipette invariably slowed endocytosis, even in terminals dialyzed with increased Ca2+ buffer. These results suggest a new role for GABA and Cl- ions in blocking the trigger for fast endocytosis at this ribbon-type synapse.
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U2 - 10.1016/j.neuron.2004.10.010
DO - 10.1016/j.neuron.2004.10.010
M3 - Article
C2 - 15504327
AN - SCOPUS:7044233444
SN - 0896-6273
VL - 44
SP - 469
EP - 482
JO - Neuron
JF - Neuron
IS - 3
ER -