title: Halothane modulates NMDA and non-NMDA excitatory synaptic transmission in rat cortical neurons.
abstract: OBJECTIVE
  Although general anesthetics may decrease neuronal excitation, their detailed effects on spontaneous excitatory postsynaptic currents (EPSCs) remain controversial. We investigated and compared the effects of halothane on N-methyl-D-asparate (NMDA) and non-NMDA receptor-mediated postsynaptic currents.
  
  
  METHODS
  Spontaneous synaptic currents were recorded by the patch clamp technique in cultured rat cortical neurons. They were isolated by specific pharmacological blocking agents and their electrophysiologic properties were examined.
  
  
  RESULTS
  The frequency of NMDA EPSCs was preferentially decreased as compared with that of non-NMDA EPSCs at halothane 1.2 mM. The total net charge of EPSCs mediated by NMDA and non-NMDA receptors was depressed to 56% +/- 6% (mean +/- SD) and 71% +/- 7% of control by halothane 0.6 mM, and to 11% +/- 9% and 59% +/- 11% of control by halothane 1.2 mM, respectively.
  
  
  CONCLUSIONS
  These results show that halothane causes decrease of excitatory synaptic activity, with NMDA EPSCs being more sensitive than non-NMDA EPSCs.
authors.affiliation: Department of Anesthesiology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-9603, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kitamura
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Satoh
authors.forename: Tomoo
authors.initials: T
authors.lastname: Nagano
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Matsuda
authors.forename: Toru
authors.initials: T
authors.lastname: Shimizu
authors.forename: Atsuhiro
authors.initials: A
authors.lastname: Sakamoto
authors.forename: Ryo
authors.initials: R
authors.lastname: Ogawa
mesh_terms: D000465:Algorithms; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D002540:Cerebral Cortex / Q000166:cytology* / Q000187:drug effects; D004594:Electrophysiology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects*; D005971:Glutamates / Q000502:physiology; D006221:Halothane / Q000494:pharmacology*; D007700:Kinetics; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects*; D009435:Synaptic Transmission / Q000187:drug effects*; D005680:gamma-Aminobutyric Acid / Q000502:physiology
chemical_list: D018685:Anesthetics, Inhalation; D005971:Glutamates; D016194:Receptors, N-Methyl-D-Aspartate; D005680:gamma-Aminobutyric Acid; D006221:Halothane