Class I metabotropic glutamate receptor agonists do not facilitate the induction of long-term potentiation in the dentate gyrus of the rat in vitro.

Abstract

The possibility that activation of class I (phospholipase C-coupled) metabotropic glutamate receptors (mGluRs) can facilitate the induction of long-term potentiation (LTP) was investigated in the dentate gyrus of rat hippocampal slices. In the presence of picrotoxin, a weak tetanus led to a short-term potentiation (STP) lasting 10-15 min. Application of the class I mGluR agonists trans-azetidine-2,4-dicarboxylic acid (tADA, 100 microM) or 3,5-dihydroxyphenylglycine (DHPG, 100 microM) for 15 or 30 min before the weak tetanus did not affect baseline synaptic transmission or the magnitude of the subsequent potentiation. DHPG (70 microM) did, however, reduce accommodation of neuronal firing in response to depolarizing current injection. These results suggest that at the medial perforant path-granule cell synapse, class I mGluR activation by exogenous agonist application does not facilitate the induction of LTP.

• Authors: R E Brown, K G Reymann
• Journal: Neuroscience letters (Neurosci Lett) Vol. 202 Issue 1-2 Pg. 73-6 (Dec 29 1995) ISSN: 0304-3940 [Print] Ireland
• PMID: 8787834 (Publication Type: Journal Article)

Chemical References

• Excitatory Amino Acid Agonists
• Excitatory Amino Acid Antagonists
• Receptors, Metabotropic Glutamate
• Resorcinols
• Picrotoxin
• azetidine-2,4-dicarboxylic acid
• Azetidinecarboxylic Acid
• 3,5-dihydroxyphenylglycine
• Glycine

Topics

• Animals
• Azetidinecarboxylic Acid (analogs & derivatives, pharmacology)
• Dentate Gyrus (physiology, ultrastructure)
• Electrophysiology
• Excitatory Amino Acid Agonists (pharmacology)
• Excitatory Amino Acid Antagonists (pharmacology)
• Glycine (analogs & derivatives, pharmacology)
• Long-Term Potentiation (drug effects)
• Male
• Picrotoxin (pharmacology)
• Rats
• Rats, Wistar
• Receptors, Metabotropic Glutamate (agonists)
• Resorcinols (pharmacology)