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Updated: Aug 15, 2026
Two-photon Calcium Imaging in Neuronal Dendrites in Brain Slices
Published on: March 15, 2018
Subthreshold synaptic Ca2+ signalling in fine dendrites and spines of cerebellar Purkinje neurons
J Eilers1, G J Augustine, A Konnerth
1I. Physiologisches Institut, Universität des Saarlandes, Homburg, Germany.
Abstract:
The conventional view of synaptic integration is that it results from the simple summation of electrical signals produced by each active synapse innervating a given neuron. However, because synaptic action can go beyond the production of postsynaptic electrical signals, to include intracellular biochemical events such as the generation of second messengers, it is possible that synaptic integration could occur at another level. We have considered this possibility by examining changes in the dendritic concentration of the second messenger, calcium, resulting from subthreshold excitatory synaptic activity in cerebellar Purkinje neurons. We report here clear evidence that such non-electrical synaptic integration occurs and that it takes place in restricted dendritic compartments consisting of spines and adjacent fine dendrites.
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