TY - JOUR
T1 - Fast synaptic vesicle reuse slows the rate of synaptic depression in the CA1 region of hippocampus
AU - Ertunc, Mert
AU - Sara, Yildirim
AU - Chung, ChiHye
AU - Atasoy, Deniz
AU - Virmani, Tuhin
AU - Kavalali, Ege T.
PY - 2007/1/10
Y1 - 2007/1/10
N2 - During short-term synaptic depression, neurotransmission rapidly decreases in response to repetitive action potential firing. Here, by blocking the vacuolar ATPase, alkalinizing the extracellular pH, or exposing hippocampal slices to pH buffers, we impaired neurotransmitter refilling, and electrophysiologically tested the role of vesicle reuse in synaptic depression. Under all conditions, synapses onto hippocampal CA1 pyramidal cells showed faster depression with increasing stimulation frequencies. At 20 Hz, compromising neurotransmitter refilling increased depression within 300 ms reaching completion within 2 s, suggesting a minimal contribution of reserve vesicles to neurotransmission. In contrast, at 1 Hz, depression emerged gradually and became significant within 100 s. Moreover, the depression induced by pH buffers was reversible with a similar frequency dependence, suggesting that the frequency-dependent increase in depression was caused by impairment of rapid synaptic vesicle reuse. These results indicate that synaptic vesicle trafficking impacts the kinetics of short-term synaptic plasticity at an extremely rapid time scale.
AB - During short-term synaptic depression, neurotransmission rapidly decreases in response to repetitive action potential firing. Here, by blocking the vacuolar ATPase, alkalinizing the extracellular pH, or exposing hippocampal slices to pH buffers, we impaired neurotransmitter refilling, and electrophysiologically tested the role of vesicle reuse in synaptic depression. Under all conditions, synapses onto hippocampal CA1 pyramidal cells showed faster depression with increasing stimulation frequencies. At 20 Hz, compromising neurotransmitter refilling increased depression within 300 ms reaching completion within 2 s, suggesting a minimal contribution of reserve vesicles to neurotransmission. In contrast, at 1 Hz, depression emerged gradually and became significant within 100 s. Moreover, the depression induced by pH buffers was reversible with a similar frequency dependence, suggesting that the frequency-dependent increase in depression was caused by impairment of rapid synaptic vesicle reuse. These results indicate that synaptic vesicle trafficking impacts the kinetics of short-term synaptic plasticity at an extremely rapid time scale.
KW - CA1
KW - Endocytosis
KW - Hippocampal slice
KW - Schaffer collateral
KW - Short term synaptic depression
KW - Synaptic vesicle recycling
KW - Vesicle reacidification
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U2 - 10.1523/JNEUROSCI.4051-06.2007
DO - 10.1523/JNEUROSCI.4051-06.2007
M3 - Article
C2 - 17215395
AN - SCOPUS:33846265638
SN - 0270-6474
VL - 27
SP - 341
EP - 354
JO - Journal of Neuroscience
JF - Journal of Neuroscience
IS - 2
ER -