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Updated: Oct 1, 2026
Vibrodissociation of Neurons from Rodent Brain Slices to Study Synaptic Transmission and Image Presynaptic Terminals
Published on: May 25, 2011
Synapsin I partially dissociates from synaptic vesicles during exocytosis induced by electrical stimulation
F Torri Tarelli1, M Bossi, R Fesce
1B. Ceccarelli Center, Department of Pharmacology, Consiglio Nazionale delle Ricerche, Center of Cytopharmacology, Milan, Italy.
Abstract:
The distribution of the synaptic vesicle-associated phosphoprotein synapsin I after electrical stimulation of the frog neuromuscular junction was investigated by immunogold labeling and compared with the distribution of the integral synaptic vesicle protein synaptophysin. In resting terminals both proteins were localized exclusively on synaptic vesicles. In stimulated terminals they appeared also in the axolemma and its infoldings, which however exhibited a lower synapsin I/synaptophysin ratio with respect to synaptic vesicles at rest. The value of this ratio was intermediate in synaptic vesicles of stimulated terminals, and an increased synapsin I labeling of the cytomatrix was observed. These results indicate that synapsin I undergoes partial dissociation from and reassociation with synaptic vesicles, following physiological stimulation, and are consistent with the proposed modulatory role of the protein in neurotransmitter release.
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