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Updated: Aug 17, 2026

Vibrodissociation of Neurons from Rodent Brain Slices to Study Synaptic Transmission and Image Presynaptic Terminals
Published on: May 25, 2011
Modulation of presynaptic store calcium induces release of glutamate and postsynaptic firing
Geeta Sharma1, Sukumar Vijayaraghavan
1Department of Physiology and Biophysics and The Neuroscience Program, University of Colorado Health Sciences Center, Denver, CO 80262, USA.
Abstract:
Action potential-independent transmitter release is random and produces small depolarizations in the postsynaptic neuron. This process is, therefore, not thought to play a significant role in impulse propagation across synapses. Here we show that calcium flux through presynaptic neuronal nicotinic receptors leads to mobilization of store calcium by calcium-induced calcium release. Recruitment of store calcium induces vesicular release of glutamate in a manner consistent with synchronization across multiple active zones in the CA3 region of the rat hippocampus. This modulation of action potential-independent release of glutamate is sufficient to drive the postsynaptic pyramidal cell above its firing threshold, thus providing a mechanism for impulse propagation.
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