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Updated: Jul 18, 2025

Measuring Synaptic Vesicle Endocytosis in Cultured Hippocampal Neurons
Published on: September 4, 2017
Roles and Sources of Calcium in Synaptic Exocytosis
Zhao-Wen Wang1, Sadaf Riaz2, Longgang Niu2
1Department of Neuroscience, University of Connecticut School of Medicine, Farmington, CT, USA. zwwang@uchc.edu.
Abstract:
Calcium ions (Ca2+) play a critical role in triggering neurotransmitter release. The rate of release is directly related to the concentration of Ca2+ at the presynaptic site, with a supralinear relationship. There are two main sources of Ca2+ that trigger synaptic vesicle fusion: influx through voltage-gated Ca2+ channels in the plasma membrane and release from the endoplasmic reticulum via ryanodine receptors. This chapter will cover the sources of Ca2+ at the presynaptic nerve terminal, the relationship between neurotransmitter release rate and Ca2+ concentration, and the mechanisms that achieve the necessary Ca2+ concentrations for triggering synaptic exocytosis at the presynaptic site.
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