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Updated: Jul 3, 2026

Presynaptic Dopamine Dynamics in Striatal Brain Slices with Fast-scan Cyclic Voltammetry
Published on: January 12, 2012
Voltage-operated Ca2+ channels regulate dopamine release from somata of dopamine neurons in the substantia nigra pars
Yonjung Kim1, Myoung Kyu Park, Sungkwon Chung
1Department of Physiology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Jangan-ku, Suwon 440-746, South Korea.
Abstract:
Dopamine (DA) neurons release DA not only from axon terminals at the striatum, but from their somata and dendrites at the substantia nigra pars compacta (SNc). Released DA may auto-regulate further DA release or modulate non-DA cells. However, the actual mechanism of somatodendritic DA release, especially the Ca(2+) dependency of the process, remains controversial. In this study, we used amperometry to monitor DA release from somata of acutely isolated rat DA neurons. We found that DA neurons spontaneously released DA in the resting state. Removal of extracellular Ca(2+) and application of blockers for voltage-operated Ca(2+) channels (VOCCs) suppressed the frequency of secretion events. Activation of VOCCs by stimulation with K(+)-rich saline increased the frequency of secretion events, which were also sensitive to blockers for L- and T-type Ca(2+) channels. These results suggest that Ca(2+) influx through VOCCs regulates DA release from somata of DA neurons.
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