Reversal of hippocampal LTP by spontaneous seizure-like activity: role of group I mGluR and cell depolarization.

@article{Hu2005ReversalOH,
  title={Reversal of hippocampal LTP by spontaneous seizure-like activity: role of group I mGluR and cell depolarization.},
  author={Bin Hu and Sergei V. Karnup and Lei Zhou and Armin Stelzer},
  journal={Journal of neurophysiology},
  year={2005},
  volume={93 1},
  pages={
          316-36
        }
}
Memory impairment is a common consequence of epileptic seizures. The hippocampal formation is particularly prone to seizure-induced amnesia due to its prominent role in mnemonic processes. We used the isolated CA1 slice preparation to examine effects of seizure-like activity on hippocampal plasticity, long-term potentiation (LTP), and long-term depression (LTD). Repeated spontaneous ictal events, generated in the presence of antagonists of GABA(A) receptor function, led to a stepwise erasure of… 
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Transient Switching of NMDA-Dependent Long-Term Synaptic Potentiation in CA3-CA1 Hippocampal Synapses to mGluR1-Dependent Potentiation After Pentylenetetrazole-Induced Acute Seizures in Young Rats
TLDR
The results revealed that LTP was strongly attenuated in the CA1 hippocampal area after PTZ-induced SE as compared with that in control animals, suggesting that transient switching between NMDA-dependent LTP and mGluR1- dependent LTP could play a role in the pathogenesis of acquired epilepsy.
Modulation by group 1 metabotropic glutamate receptors of depotentiation in the dentate gyrus of freely moving rats
TLDR
It is suggested that activation of group I mGluRs mediate thresholds for depotentiation and for persistent LTP, which may be linked to the intensity and duration of the calcium signal elicited by LFS and HFT.
Time-dependent changes in learning ability and induction of long-term potentiation in the lithium–pilocarpine-induced epileptic mouse model
Effects of TRPV1 on the hippocampal synaptic plasticity in the epileptic rat brain
TLDR
Findings indicate that a higher expression of TRPV1 in epileptic conditions is accompanied by a functional impact on the synaptic plasticity in the hippocampus, which suggests TRpV1 as a potential target in treatment of seizure attacks.
Shift in induction mechanisms underlies an age-dependent increase in DHPG-induced synaptic depression at CA3 CA1 synapses.
TLDR
Examination of age-related changes in the induction of group I metabotropic receptor selective agonist (R,S)-3,5-dihydroxyphenylglycine induced long-term synaptic depression (DHPG-LTD) at CA3-CA1 synapses provides evidence that DHPG- LTD is one of the few forms of synaptic plasticity that increases with advanced age and suggests that DHGP may contribute to age- related changes in hippocampal function.
Hippocampal NPY gene transfer attenuates seizures without affecting epilepsy-induced impairment of LTP
Chronic but not acute immobilization stress stably enhances hippocampal CA1 metabotropic glutamate receptor dependent Long-Term Depression
Role of metabotropic glutamate receptors in persistent forms of hippocampal plasticity and learning
Epileptic pilocarpine‐treated rats exhibit aberrant hippocampal EPSP‐spike potentiation but retain long‐term potentiation
TLDR
LTP and E‐S potentiation have overlapping but nonidentical mechanisms of inducing neuronal plasticity that may independently contribute to cognitive disruptions observed in the chronic epileptic state.
Rescue of hippocampal LTP and learning deficits in a rat model of psychosis by inhibition of glycine transporter‐1 (GlyT1)
TLDR
Treatment with a glycine transporter inhibitor can ameliorate deficits in both LTP and learning that occur in a rat model of psychosis, and may therefore prove a useful strategy to address cognitive disruption in psychotic illnesses.
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