Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

We have studied the effects of groups II and III metabotropic glutamate receptor (mGluR) activation on excitatory responses recorded from hippocampal interneurons of CA1 stratum lacunosum moleculare (SLM). Excitatory postsynaptic currents (EPSCs) evoked by stimulation of the perforant pathway were reduced either by the group II mGluR agonist LY354740 (50-100 nM, 49.1+/-5.7% of control) or by the group III mGluR agonist l-2-amino-4-phosphonobutyric acid (l-AP4) (50 microM, 36.8+/-4.4% of control). Both drugs significantly enhanced paired-pulse facilitation of the EPSCs. Furthermore, both 100 nM LY354740 and 50 microM l-AP4 reduced the frequency, but not the amplitude, of miniature excitatory synaptic currents (mEPSCs), recorded in the presence of 1 microM TTX and 50 microM picrotoxin, or EPSCs evoked by perforant pathway stimulation in the presence of 2.5 mM Sr2+. The broad-spectrum mGluR antagonist LY341495 (10-50 microM) did not affect test EPSCs elicited 210 ms after stimulation at 100 Hz. At network level, 1-5 microM LY354740 significantly reduced the power of gamma frequency oscillations induced by 20 microM carbachol, 600 nM kainate and 5 mM K+ in hippocampal CA1 area. Our results show powerful modulation of excitatory transmission impinging on interneurons of CA1 SLM by presynaptic group II or III mGluRs.

Original publication

DOI

10.1016/j.neuropharm.2005.05.009

Type

Journal article

Journal

Neuropharmacology

Publication Date

2005

Volume

49 Suppl 1

Pages

45 - 56

Keywords

Amino Acids, Aminobutyrates, Analysis of Variance, Animals, Animals, Newborn, Bridged Bicyclo Compounds, Electric Stimulation, Excitatory Amino Acid Agonists, Excitatory Amino Acid Antagonists, Excitatory Postsynaptic Potentials, Hippocampus, In Vitro Techniques, Interneurons, Neural Inhibition, Perforant Pathway, Presynaptic Terminals, Rats, Rats, Sprague-Dawley, Receptors, Metabotropic Glutamate, Strontium, Tetrodotoxin, Time Factors, Xanthenes