The Recurrent Mossy Fiber Pathway of the Epileptic Brain

@article{Nadler2004TheRM,
  title={The Recurrent Mossy Fiber Pathway of the Epileptic Brain},
  author={J. Victor Nadler},
  journal={Neurochemical Research},
  year={2004},
  volume={28},
  pages={1649-1658}
}
  • J. Nadler
  • Published 2004
  • Biology, Medicine
  • Neurochemical Research
The dentate gyrus is believed to play a key role in the pathogenesis of temporal lobe epilepsy. In normal brain the dentate granule cells serve as a high-resistance gate or filter, inhibiting the propagation of seizures from the entorhinal cortex to the hippocampus. The filtering function of the dentate gyrus depends in part on the near absence of monosynaptic connections among granule cells. In humans with temporal lobe epilepsy and in animal models of temporal lobe epilepsy, dentate granule… Expand
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Highly Influential Citations
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Background Citations
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Methods Citations
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Results Citations
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256 Citations

Citation Type

Citation Type

PLASTICITY | Axon Sprouting in Epilepsy
TLDR
Issues include: the circumstances under which reverberating excitation overcomes homeostatic restraints to synchronize population bursts, the mechanisms by which dentate gyrus inhibition recovers from the seizure-induced loss of GABA interneurons, the precise role of hilar ectopic granule cells in seizure propagation, and the extent to which reorganization of brain circuitry accounts for cognitive/behavioral dysfunction in persons with lesional epilepsy. Expand
Recurrent Mossy Fibers Establish Aberrant Kainate Receptor-Operated Synapses on Granule Cells from Epileptic Rats
TLDR
It is reported that KARs are involved in ongoing glutamatergic transmission in granule cells from chronic epileptic but not control animals, and KAR-mediated EPSCKAs are selectively generated by recurrent mossy fiber inputs and have a slower kinetics than EPSCAMPA. Expand
Neuropeptide Y regulates recurrent mossy fiber synaptic transmission less effectively in mice than in rats: Correlation with Y2 receptor plasticity
TLDR
Two contrasting receptor changes can explain the quantitatively different effects of endogenously released and applied NPY on recurrent mossy fiber transmission in mice and rats. Expand
Neuropeptide Y in the recurrent mossy fiber pathway
TLDR
The recurrent mossy fiber pathway may synchronize granule cell discharge more effectively in humans and mice than in rats, due to its lower expression of either NPY (humans) or Y2 receptors (mice). Expand
Facilitation of granule cell epileptiform activity by mossy fiber-released zinc in the pilocarpine model of temporal lobe epilepsy
TLDR
It is suggested that zinc released from the recurrent mossy fibers serves mainly to facilitate the recruitment of dentate granule cells into population bursts. Expand
Properties of Dentate Granule Cells and Their Relevance to Seizures
Encoding into declarative memory of the distinct temporal and spatial relationships comprising events depends on the activity of dentate granule cells. This component of memory formation is referred… Expand
Plasticity of Dentate Granule Cell Mossy Fiber Synapses: A Putative Mechanism of Limbic Epileptogenesis
The epilepsies constitute the third most common serious neurological disorder. Among the more than 40 different types of epilepsy, limbic epilepsy is the single most common and devastating form.… Expand
Enhanced Synaptic Connectivity in the Dentate Gyrus during Epileptiform Activity: Network Simulation
TLDR
Computer modelling of the dentate gyrus circuitry and the corresponding structural changes has been used to understand how abnormal mossy fibre sprouting can subserve seizure generation observed in experimental models when epileptogenesis is induced by status epilepticus and suggest that there is a joint action of the compensation theory and Hebbian rules during the inflammatory process that accompanies the status epileptus. Expand
Spontaneous Release of Neuropeptide Y Tonically Inhibits Recurrent Mossy Fiber Synaptic Transmission in Epileptic Brain
TLDR
Tonic release of NPY accounts at least partially for the low probability of glutamate release from recurrent mossy fiber terminals, impedes the ability of these fibers to synchronize granule cell discharge, and may protect the hippocampus from seizures that involve the entorhinal cortex. Expand
Status Epilepticus Induced Spontaneous Dentate Gyrus Spikes: In Vivo Current Source Density Analysis
TLDR
Dentate spikes are investigated following status epilepticus to suggest that following SE there is an increase in DS activity, potentially arising from hyperexcitability along the hippocampal-entorhinal pathway or within the dentate gyrus itself. Expand
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References

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TLDR
The results suggest that the recurrent mossy fiber pathway may be functionally silent during baseline asynchronous granule cell activity in vivo attributable, in part, to progressive transmission failure. Expand
Recurrent mossy fiber pathway in rat dentate gyrus: synaptic currents evoked in presence and absence of seizure-induced growth.
TLDR
The hypothesis that recurrent mossy fiber growth and synapse formation increases the excitatory drive to dentate granule cells and thus facilitates repetitive synchronous discharge is supported. Expand
Electrophysiology of dentate granule cells after kainate-induced synaptic reorganization of the mossy fibers
TLDR
Recordings from granule cells in hippocampal slices removed from rats 1-4 months after kainate treatment suggest that new local excitatory circuits may be suppressed normally, and then emerge functionally when synaptic inhibition is blocked, and suggest that after repeated seizures and excitotoxic damage in the hippocampus, synaptic reorganization of the mossy fibers is consistently associated with normal responses. Expand
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TLDR
Results indicate that even modest changes in [K(+)](o) dramatically affect granule cell epileptiform activity supported by the recurrent mossy fiber pathway, and that block of GABA(A) receptor-mediated inhibition is less efficacious and frequency facilitation may not be a significant factor. Expand
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TLDR
The strong similarity between responses from the status epilepticus and control groups suggests that they resulted from activation of a similar synaptic population, and new synapses appear to operate very similarly to preexisting mossy fiber-granule cell synapses. Expand
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TLDR
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TLDR
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TLDR
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Lack of effect of mossy fiber-released zinc on granule cell GABA(A) receptors in the pilocarpine model of epilepsy.
TLDR
The results suggest that zinc released from the recurrent mossy fiber pathway did not reach a concentration at postsynaptic GABA(A) receptors sufficient to inhibit agonist-evoked activation. Expand
Status epilepticus‐induced hilar basal dendrites on rodent granule cells contribute to recurrent excitatory circuitry
TLDR
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