The Recurrent Mossy Fiber Pathway of the Epileptic Brain

  title={The Recurrent Mossy Fiber Pathway of the Epileptic Brain},
  author={J. Victor Nadler},
  journal={Neurochemical Research},
  • J. Nadler
  • Published 1 November 2003
  • Biology
  • 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… 

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Recurrent mossy fiber pathway in rat dentate gyrus: synaptic currents evoked in presence and absence of seizure-induced growth.

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.

Modest increase in extracellular potassium unmasks effect of recurrent mossy fiber growth.

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.

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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.

Mossy fiber synaptic reorganization in the epileptic human temporal lobe

The results are morphological evidence of mossy Fiber synaptic reorganization in the temporal lobe of epileptic humans, and suggest the intriguing possibility that mossy fiber sprouting and synaptic reorganizing induced by repeated partial complex seizures may play a role in human epilepsy.

NMDA receptor-dependent plasticity of granule cell spiking in the dentate gyrus of normal and epileptic rats.

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Status epilepticus‐induced hilar basal dendrites on rodent granule cells contribute to recurrent excitatory circuitry

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