TY - JOUR
T1 - Optimizing synaptic architecture and efficiency for high-frequency transmission
AU - Taschenberger, Holger
AU - Leão, Ricardo M.
AU - Rowland, Kevin C.
AU - Spirou, George A.
AU - Von Gersdorff, Henrique
N1 - Funding Information:
We thank Craig Jahr for comments on the manuscript and Larry Trussell and George D. Pollack for valuable discussions. Janelle Grimes and Brian Pope provided expert technical assistance with electron microscopy. H.T. was partially funded by a HFSP fellowship. H.v.G. was funded by a NIH/NIDCD grant and a Pew Biomedical Research Scholar grant. G.S. was supported by NIH COBRE Grant P20 RR15574, project #4.
PY - 2002/12/19
Y1 - 2002/12/19
N2 - Bursts of neuronal activity are transmitted more effectively as synapses mature. However, the mechanisms that control synaptic efficiency during development are poorly understood. Here, we study postnatal changes in synaptic ultrastructure and exocytosis in a calyx-type nerve terminal. Vesicle pool size, exocytotic efficiency (amount of exocytosis per Ca influx), Ca current facilitation, and the number of active zones (AZs) increased with age, whereas AZ area, number of docked vesicles per AZ, and release probability decreased with age. These changes led to AZs that are less prone to multivesicular release, resulting in reduced AMPA receptor saturation and desensitization. A greater multiplicity of small AZs with few docked vesicles, a larger pool of releasable vesicles, and a higher efficiency of release thus promote prolonged high-frequency firing in mature synapses.
AB - Bursts of neuronal activity are transmitted more effectively as synapses mature. However, the mechanisms that control synaptic efficiency during development are poorly understood. Here, we study postnatal changes in synaptic ultrastructure and exocytosis in a calyx-type nerve terminal. Vesicle pool size, exocytotic efficiency (amount of exocytosis per Ca influx), Ca current facilitation, and the number of active zones (AZs) increased with age, whereas AZ area, number of docked vesicles per AZ, and release probability decreased with age. These changes led to AZs that are less prone to multivesicular release, resulting in reduced AMPA receptor saturation and desensitization. A greater multiplicity of small AZs with few docked vesicles, a larger pool of releasable vesicles, and a higher efficiency of release thus promote prolonged high-frequency firing in mature synapses.
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U2 - 10.1016/S0896-6273(02)01137-6
DO - 10.1016/S0896-6273(02)01137-6
M3 - Article
C2 - 12495627
AN - SCOPUS:0037137693
SN - 0896-6273
VL - 36
SP - 1127
EP - 1143
JO - Neuron
JF - Neuron
IS - 6
ER -