scholarly journals Climbing fiber coupling between adjacent Purkinje cell dendrites in vivo

2009 ◽  
Vol 3 ◽  
Author(s):  
Fredrik Bengtsson
Keyword(s):  
Purkinje Cell ◽  
Climbing Fiber ◽  
Fiber Coupling ◽  
Purkinje Cell Dendrites

scholarly journals Conversion of graded presynaptic climbing fiber activity into graded postsynaptic Ca2+ signals by Purkinje cell dendrites

2018 ◽  
Author(s):  
Michael A. Gaffield ◽  
Jason M. Christie
Keyword(s):  
Purkinje Cell ◽  
Inferior Olive ◽  
Mossy Fiber ◽  
Climbing Fiber ◽  
Climbing Fibers ◽  
Dependent Manner ◽  
Related Information ◽  
External Stimuli ◽  
Purkinje Cell Dendrites

AbstractThe brain must make sense of external stimuli to generate relevant behavior. We used a combination of in vivo approaches to investigate how the cerebellum processes sensory-related information. We found that the inferior olive encodes contexts of sensory-associated external cues in a graded manner, apparent in the presynaptic activity of their axonal projections in the cerebellar cortex. Further, individual climbing fibers were broadly responsive to different sensory modalities but relayed sensory-related information to the cortex in a lobule-dependent manner. Purkinje cell dendrites faithfully transformed this climbing fiber activity into dendrite-wide Ca2+ signals without a direct contribution from the mossy fiber pathway. These results demonstrate that the size of climbing fiber-evoked Ca2+ signals in Purkinje cell dendrites is largely determined by the firing level of climbing fibers. This coding scheme emphasizes the overwhelming role of the inferior olive in generating salient signals useful for instructing plasticity and learning.

scholarly journals Activity-Dependent Gating of Calcium Spikes by A-type K+ Channels Controls Climbing Fiber Signaling in Purkinje Cell Dendrites

Neuron ◽  
2014 ◽  
Vol 84 (1) ◽  
pp. 137-151 ◽  
Author(s):  
Yo Otsu ◽  
Païkan Marcaggi ◽  
Anne Feltz ◽  
Philippe Isope ◽  
Mihaly Kollo ◽  
...  
Keyword(s):  
Purkinje Cell ◽  
Climbing Fiber ◽  
Calcium Spikes ◽  
K Channels ◽  
Type K ◽  
Activity Dependent ◽  
Purkinje Cell Dendrites

scholarly journals In Vivo Analysis of the Climbing Fiber-Purkinje Cell Circuit in SCA2-58Q Transgenic Mouse Model

2018 ◽  
Vol 17 (5) ◽  
pp. 590-600 ◽  
Author(s):  
Polina A. Egorova ◽  
Alexandra V. Gavrilova ◽  
Ilya B. Bezprozvanny
Keyword(s):  
Mouse Model ◽  
Purkinje Cell ◽  
Transgenic Mouse ◽  
Transgenic Mouse Model ◽  
Climbing Fiber ◽  
In Vivo Analysis ◽  
Cell Circuit

scholarly journals βIII spectrin controls the planarity of Purkinje cell dendrites by modulating perpendicular axon-dendrite interactions

Development ◽  
2020 ◽  
Vol 147 (24) ◽  
pp. dev194530
Author(s):  
Kazuto Fujishima ◽  
Junko Kurisu ◽  
Midori Yamada ◽  
Mineko Kengaku
Keyword(s):  
Purkinje Cell ◽  
Neural Circuits ◽  
Model System ◽  
Spinocerebellar Ataxia Type ◽  
Crucial Importance ◽  
Electrospun Nanofiber ◽  
Oriented Growth ◽  
Branch Formation ◽  
Purkinje Cell Dendrites

ABSTRACTThe mechanism underlying the geometrical patterning of axon and dendrite wiring remains elusive, despite its crucial importance in the formation of functional neural circuits. The cerebellar Purkinje cell (PC) arborizes a typical planar dendrite, which forms an orthogonal network with granule cell (GC) axons. By using electrospun nanofiber substrates, we reproduce the perpendicular contacts between PC dendrites and GC axons in culture. In the model system, PC dendrites show a preference to grow perpendicularly to aligned GC axons, which presumably contribute to the planar dendrite arborization in vivo. We show that βIII spectrin, a causal protein for spinocerebellar ataxia type 5, is required for the biased growth of dendrites. βIII spectrin deficiency causes actin mislocalization and excessive microtubule invasion in dendritic protrusions, resulting in abnormally oriented branch formation. Furthermore, disease-associated mutations affect the ability of βIII spectrin to control dendrite orientation. These data indicate that βIII spectrin organizes the mouse dendritic cytoskeleton and thereby regulates the oriented growth of dendrites with respect to the afferent axons.

scholarly journals Increased Climbing Fiber Lateral Crossings on Purkinje Cell Dendrites in the Cerebellar Hemisphere in Essential Tremor

2021 ◽  
Author(s):  
Yueh‐Chi Wu ◽  
Elan D. Louis ◽  
John Gionco ◽  
Ming‐Kai Pan ◽  
Phyllis L. Faust ◽  
...  
Keyword(s):  
Purkinje Cell ◽  
Essential Tremor ◽  
Climbing Fiber ◽  
Cerebellar Hemisphere ◽  
Purkinje Cell Dendrites

scholarly journals Coding of stimulus strength via analog calcium signals in Purkinje cell dendrites of awake mice

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Farzaneh Najafi ◽  
Andrea Giovannucci ◽  
Samuel S-H Wang ◽  
Javier F Medina
Keyword(s):  
Purkinje Cell ◽  
Purkinje Cells ◽  
Eyeblink Conditioning ◽  
Climbing Fiber ◽  
Stimulus Strength ◽  
Calcium Signals ◽  
Calcium Spikes ◽  
Conditioning Information ◽  
Teaching Signal ◽  
Purkinje Cell Dendrites

The climbing fiber input to Purkinje cells acts as a teaching signal by triggering a massive influx of dendritic calcium that marks the occurrence of instructive stimuli during cerebellar learning. Here, we challenge the view that these calcium spikes are all-or-none and only signal whether the instructive stimulus has occurred, without providing parametric information about its features. We imaged ensembles of Purkinje cell dendrites in awake mice and measured their calcium responses to periocular airpuffs that serve as instructive stimuli during cerebellar-dependent eyeblink conditioning. Information about airpuff duration and pressure was encoded probabilistically across repeated trials, and in two additional signals in single trials: the synchrony of calcium spikes in the Purkinje cell population, and the amplitude of the calcium spikes, which was modulated by a non-climbing fiber pathway. These results indicate that calcium-based teaching signals in Purkinje cells contain analog information that encodes the strength of instructive stimuli trial-by-trial.

An active membrane model of the cerebellar Purkinje cell II. Simulation of synaptic responses

1994 ◽  
Vol 71 (1) ◽  
pp. 401-419 ◽  
Author(s):  
E. De Schutter ◽  
J. M. Bower
Keyword(s):  
Purkinje Cell ◽  
Purkinje Cells ◽  
Average Frequency ◽  
Climbing Fiber ◽  
Cerebellar Purkinje Cell ◽  
Inhibitory Synapses ◽  
Complex Spike ◽  
Simple Spike ◽  
Spike Firing

1. Both excitatory and inhibitory postsynaptic channels were added to a previously described complex compartmental model of a cerebellar Purkinje cell to examine model responses to synaptic inputs. All model parameters remained as described previously, leaving maximum synaptic conductance as the only parameter that was tuned in the studies described in this paper. Under these conditions the model was capable of reproducing physiological recorded responses to each of the major types of synaptic input. 2. When excitatory synapses were activated on the smooth dendrites of the model, the model generated a complex dendritic Ca2+ spike similar to that generated by climbing fiber inputs. Examination of the model showed that activation of P-type Ca2+ channels in both the smooth and spiny dendrites augmented the depolarization during the complex spike and that Ca(2+)-activated K+ channels in the same dendritic regions determined the duration of the spike. When these synapses were activated under simulated current-clamp conditions the model also generated the characteristic dual reversal potential of the complex spike. The shape of the dendritic complex spike could be altered by changing the maximum conductance of the climbing fiber synapse and thus the amount of Ca2+ entering the cell. 3. To explore the background simple spike firing properties of Purkinje cells in vivo we added excitatory “parallel fiber” synapses to the spiny dendritic branches of the model. Continuous asynchronous activation of these granule cell synapses resulted in the generation of spontaneous sodium spikes. However, very low asynchronous input frequencies produced a highly regular, very fast rhythm (80–120 Hz), whereas slightly higher input frequencies resulted in Purkinje cell bursting. Both types of activity are uncharacteristic of in vivo Purkinje cell recordings. 4. Inhibitory synapses of the sort presumably generated by stellate cells were also added to the dendritic tree. When asynchronous activation of these inhibitory synapses was combined with continuous asynchronous excitatory input the model generated somatic action potentials in a much more stochastic pattern typical of real Purkinje cells. Under these conditions simulated inter-spike interval distributions resembled those found in experimental recordings. Also, as with in vivo recordings, the model did not generate dendritic bursts. This was mainly due to inhibition that suppressed the generation of dendritic Ca2+ spikes. 5. In the presence of asynchronous inhibition, changes in the average frequency of excitatory inputs modulated background simple spike firing frequencies in the natural range of Purkinje cell firing frequencies (30–100 Hz). This modulation was very sensitive to small changes in the average frequency of excitatory inputs.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Inhibition gates supralinear Ca2+ signaling in Purkinje cell dendrites during practiced movements

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Michael A Gaffield ◽  
Matthew J M Rowan ◽  
Samantha B Amat ◽  
Hirokazu Hirai ◽  
Jason M Christie
Keyword(s):  
Neural Circuit ◽  
Molecular Layer ◽  
Climbing Fiber ◽  
Parallel Fiber ◽  
Climbing Fibers ◽  
Parallel Fibers ◽  
Motor Behaviors ◽  
Sensorimotor Information ◽  
Purkinje Cell Dendrites

Motor learning involves neural circuit modifications in the cerebellar cortex, likely through re-weighting of parallel fiber inputs onto Purkinje cells (PCs). Climbing fibers instruct these synaptic modifications when they excite PCs in conjunction with parallel fiber activity, a pairing that enhances climbing fiber-evoked Ca2+ signaling in PC dendrites. In vivo, climbing fibers spike continuously, including during movements when parallel fibers are simultaneously conveying sensorimotor information to PCs. Whether parallel fiber activity enhances climbing fiber Ca2+ signaling during motor behaviors is unknown. In mice, we found that inhibitory molecular layer interneurons (MLIs), activated by parallel fibers during practiced movements, suppressed parallel fiber enhancement of climbing fiber Ca2+ signaling in PCs. Similar results were obtained in acute slices for brief parallel fiber stimuli. Interestingly, more prolonged parallel fiber excitation revealed latent supralinear Ca2+ signaling. Therefore, the balance of parallel fiber and MLI input onto PCs regulates concomitant climbing fiber Ca2+ signaling.

scholarly journals Conversion of Graded Presynaptic Climbing Fiber Activity into Graded Postsynaptic Ca2+ Signals by Purkinje Cell Dendrites

Neuron ◽  
2019 ◽  
Vol 102 (4) ◽  
pp. 762-769.e4 ◽  
Author(s):  
Michael A. Gaffield ◽  
Audrey Bonnan ◽  
Jason M. Christie
Keyword(s):  
Purkinje Cell ◽  
Climbing Fiber ◽  
Purkinje Cell Dendrites
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