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
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
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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
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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
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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 referredExpand
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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TLDR
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TLDR
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TLDR
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TLDR
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