Korean J Physiol Pharmacol.  2016 Nov;20(6):557-564. 10.4196/kjpp.2016.20.6.557.

Metabotropic glutamate receptor dependent long-term depression in the cortex

Affiliations
  • 1Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul 08826, Korea.
  • 2Center for Neuron and Disease, Frontier Institutes of Life Science and of Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China. kaang@snu.ac.kr
  • 3Department of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 08826, Korea.

Abstract

Metabotropic glutamate receptor (mGluR)-dependent long-term depression (LTD), a type of synaptic plasticity, is characterized by a reduction in the synaptic response, mainly at the excitatory synapses of the neurons. The hippocampus and the cerebellum have been the most extensively studied regions in mGluR-dependent LTD, and Group 1 mGluR has been reported to be mainly involved in this synaptic LTD at excitatory synapses. However, mGluR-dependent LTD in other brain regions may be involved in the specific behaviors or diseases. In this paper, we focus on five cortical regions and review the literature that implicates their contribution to the pathogenesis of several behaviors and specific conditions associated with mGluR-dependent LTD.

Keyword

Cortex; LTD; mGluR; Synaptic plasticity

MeSH Terms

Brain
Cerebellum
Depression*
Hippocampus
Neuronal Plasticity
Neurons
Receptors, Metabotropic Glutamate*
Synapses
Receptors, Metabotropic Glutamate

Figure

  • Fig. 1 Models of cortical mGluR-LTDs.(A) mGluR LTD in the ACC is mGluR1, L-VGCC and partially NMDAR dependent. (B) mGluR LTD in the IC is mGluR5, NMDAR, L-VGCC, CB1R and PP1/2A dependent. (C) mGluR LTD in the PFC is Group II mGluR, PLC, IP3, PKC and NMDAR dependent. (D) mGluR LTD in the perirhinal cortex is mGluR5, Group II mGluR and NMDAR dependent. (E) mGluR LTD in the visual cortex is Group II mGluR and NMDAR dependent.


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