Document Detail


Role of group II and III metabotropic glutamate receptors in rhythmic patterns of the neonatal rat spinal cord in vitro.
MedLine Citation:
PMID:  15007577     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Electrophysiological recordings were used to explore the role of group II and III metabotropic glutamate receptors (mGluRs) in oscillatory patterns generated by the neonatal rat spinal cord in vitro. Neither the group II agonist DCG-IV (and the selective antagonist EGLU), nor the group III agonist L-AP4 (and its selective antagonist CPPG) had any effect on lumbar motoneuron membrane potential or input resistance. This observation suggests that motoneurons expressed no functional group II and III mGluRs and received no network-based, tonic influence mediated by them. DCG-IV or L-AP4 strongly depressed synaptic responses evoked by single dorsal root (DR) stimuli, an effect counteracted by their respective antagonist. EGLU or CPPG per se had no effect on synaptic responses, indicating no mGluR autoreceptor-dependent control of transmitter release. L-AP4 largely depressed cumulative depolarization, windup and associated oscillations, whereas synaptic depression induced by DCG-IV waned with repeated stimuli. L-AP4 slowed down fictive locomotor patterns and arrested disinhibited bursting, which could, however, be promptly restored by DR electrical stimulation. DCG-IV had no significant effect on fictive locomotion, but it blocked disinhibited bursting. EGLU facilitated bursting, suggesting that burst termination was partly controlled by group II mGluRs. All these effects were reversible on washout. It is concluded that activation of group II and III mGluRs differentially modulated rhythmic patterns recorded from motoneurons via network-dependent actions, which probably included decrease in the release of neurotransmitters at key circuit points.
Authors:
Giuliano Taccola; Cristina Marchetti; Andrea Nistri
Related Documents :
15451017 - Contribution of gaba(b) receptor-mediated inhibition to the expression and termination ...
18648667 - Interaction between purkinje cells and inhibitory interneurons may create adjustable ou...
12577267 - The role of electrostatic interaction in the molecular recognition of selective agonist...
10319187 - Involvement of metabotropic glutamate receptors in taurine release in the adult and dev...
2163857 - N-methyl-d-aspartate-induced neuronal activation is selectively modulated by sigma rece...
7897507 - Anoxic ltp is mediated by the redox modulatory site of the nmda receptor.
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, Non-U.S. Gov't     Date:  2004-03-09
Journal Detail:
Title:  Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale     Volume:  156     ISSN:  0014-4819     ISO Abbreviation:  Exp Brain Res     Publication Date:  2004 Jun 
Date Detail:
Created Date:  2004-05-28     Completed Date:  2004-09-29     Revised Date:  2009-11-11    
Medline Journal Info:
Nlm Unique ID:  0043312     Medline TA:  Exp Brain Res     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  495-504     Citation Subset:  IM    
Affiliation:
Neurobiology Sector and INFM Unit, International School for Advanced Studies (SISSA), Via Beirut 4, 34014 Trieste, Italy.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Action Potentials / drug effects,  physiology
Animals
Animals, Newborn
Biological Clocks / drug effects,  physiology*
Dose-Response Relationship, Drug
Excitatory Amino Acid Agonists / pharmacology
Excitatory Amino Acid Antagonists / pharmacology
Locomotion / drug effects,  physiology
Motor Neurons / drug effects,  physiology*
Nerve Net / cytology,  drug effects,  physiology*
Neural Inhibition / drug effects,  physiology
Organ Culture Techniques
Periodicity
Rats
Receptors, Metabotropic Glutamate / agonists,  antagonists & inhibitors,  physiology*
Spinal Cord / cytology,  drug effects,  physiology*
Synaptic Transmission / drug effects,  physiology
Chemical
Reg. No./Substance:
0/Excitatory Amino Acid Agonists; 0/Excitatory Amino Acid Antagonists; 0/Receptors, Metabotropic Glutamate

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Intracranial arteriovenous fistula caused by endovascular stent-grafting and dilatation.
Next Document:  Properties of horizontal semicircular canal nerve-activated vestibulospinal neurons in cats.