𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Modulation by group 1 metabotropic glutamate receptors of depotentiation in the dentate gyrus of freely moving rats

✍ Scribed by Alexander Kulla; Denise Manahan-Vaughan

Publisher
John Wiley and Sons
Year
2007
Tongue
English
Weight
172 KB
Volume
18
Category
Article
ISSN
1050-9631

No coin nor oath required. For personal study only.

✦ Synopsis

Abstract

In the hippocampus, synaptic depression of potentiated synapses in the form of depotentiation, or of naive synapses in the form of long‐term depression (LTD) is mediated by distinct molecular mechanisms. Activation of group 1 metabotropic glutamate receptors (mGluRs) is critically required for both hippocampal long‐term potentiation (LTP) and LTD in vivo, but their involvement in depotentiation is unclear. In this study, we investigated whether this class of mGluRs contributes to depotentiation in freely moving rats. Male adult Wistar rats underwent chronic implantation of stimulating and recording electrodes in the perforant path and dentate gyrus granule cell layer, respectively, as well as an injection cannula in the ipsilateral cerebral ventricle. Robust LTP which endured for over 24 h, was induced by high frequency tetanization (HFT, 200 Hz). Depotentiation was induced with LFS (5 Hz, 600 pulses) given 5 min after the LTP‐inducing tetanus was applied. The selective group 1 mGluR antagonists, (S)‐4‐carboxyphenylglycine and (R,S)‐1‐aminoindan‐1,5‐dicarboxylic acid significantly inhibited both depotentiation and LTP. Activation of group I mGluRs leads to changes in postsynaptic intracellular calcium levels. These findings suggest that activation of group I mGluRs mediate thresholds for depotentiation and for persistent LTP. Effects may be linked to the intensity and duration of the calcium signal elicited by LFS and HFT. © 2007 Wiley‐Liss, Inc.

📜 SIMILAR VOLUMES

Modulation of long-term potentiation by
Modulation of long-term potentiation by individual subtypes of muscarinic acetylcholine receptor in the rat dentate gyrus
✍ Le Luo; Wei-Heng Chen; Ming Wang; Da-Miao Zhu; Jia-Qi She; Di-Yun Ruan 📂 Article 📅 2008 🏛 John Wiley and Sons 🌐 English ⚖ 164 KB

The roles of the muscarinic acetylcholine (ACh) receptors (mAChRs) in long-term potentiation (LTP) at many areas of the central nervous system including the hippocampus, have been extensively studied. However, not much is known about the modulation of LTP through individual subtypes of mAChR (M(1)-M

Analysis of the interaction between arac
Analysis of the interaction between arachidonic acid and metabotropic glutamate receptor activation reveals that phospholipase C acts as a coincidence detector in the expression of long-term potentiation in the rat dentate gyrus
✍ B. McGahon; M.A. Lynch 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 132 KB 👁 2 views

We have reported that arachidonic acid and the metabotropic glutamate receptor agonist, trans-1-amino-cyclopentyl-1,3-dicarboxylate (ACPD), act in synergy to increase release of glutamate from synaptosomes prepared from rat dentate gyrus. The observation that prior induction of LTP in perforant path

Seizures and neuronal damage induced in
Seizures and neuronal damage induced in the rat by activation of group I metabotropic glutamate receptors with their selective agonist 3,5-dihydroxyphenylglycine
✍ Lluïsa Camón; Pilar Vives; Núria de Vera; Emili Martínez 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 283 KB 👁 2 views

While it is well documented that the overactivation of ionotropic glutamate receptors leads to seizures and excitotoxic injury, little is known about the role of metabotropic glutamate receptors (mGluRs) in epileptogenesis and neuronal injury. Intracerebroventricular (i.c.v.) infusion of the group I