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Updated: Jul 7, 2026

Two-photon Calcium Imaging in Neuronal Dendrites in Brain Slices
Published on: March 15, 2018
Participation of low-threshold Ca2+ spike in the Purkinje cells complex spike
Pauline Cavelier1, Ann M Lohof, Etienne Lonchamp
1Department de Neurotransmission et Sécrétion Neuroendocrine, UMR7168-LC2 CNRS-Université L. Pasteur, rue Blaise Pascal, F-67084 STRASBOURG cedex, France.
Abstract:
In Purkinje cells from cerebellar slice cultures, low-threshold Ca spike (LTS) gives rise to complex bursts in the soma that resemble the complex spike induced by climbing fibers stimulation. We show that LTS is reduced by T-type and R-type Ca channel blockers (SNX-482, nickel, or mibefradil). We propose that LTS is generated by openings of T-type Ca channels (alpha-1G and/or alpha-1I subunits) and R-type Ca channels (alpha-1E subunit isoforms with a weak sensitivity to SNX-482 and to nickel). Using mibefradil we show that climbing fiber stimulation activates LTS, which contributes to the shape of the response. This Ca entry may be involved in Ca-dependent synaptic plasticity of the parallel fiber input induced by climbing fiber activation.
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