title: Low concentration of DL-2-amino-5-phosphonovalerate induces epileptiform activity in guinea pig hippocampal slices.
abstract: OBJECTIVE
  The specific mechanisms by which low concentrations of cyclosporine induce seizures and low concentrations of phencyclidine provoke behavioral excitation remain to be elucidated. Both compounds block N-methyl-d-aspartate (NMDA) receptors. The aim of this study was to determine if low concentrations of the NMDA-receptor blockers increase the seizure susceptibility.
  
  
  METHODS
  Guinea pig hippocampal slices were exposed to artificial cerebrospinal fluid containing the NMDA blocker dl-2-amino-5-phosphono-valerate (APV; 0.1-10 microM). Extracellular field potentials were recorded from CA1 and CA3 regions.
  
  
  RESULTS
  Low concentrations of APV induced epileptiform burst discharges (0.1-0.25 microM), whereas higher doses failed to decrease the seizure threshold (1-10 microM).
  
  
  CONCLUSIONS
  The results indicate that the excitatory effect of low concentrations NMDA blockers may play a role in the neurotoxicity of aforementioned substances.
authors.affiliation: Institut für Physiologie, and Institut für Experimentelle Epilepsieforschung, Universität Münster, Münster, Germany. gorjial@uni-muenster.de
authors.forename: A
authors.initials: A
authors.lastname: Gorji
authors.forename: E J
authors.initials: EJ
authors.lastname: Speckmann
mesh_terms: D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology*; D000818:Animals; D046508:Culture Techniques; D004305:Dose-Response Relationship, Drug; D004569:Electroencephalography / Q000187:drug effects*; D004827:Epilepsy / Q000139:chemically induced* / Q000503:physiopathology; D005071:Evoked Potentials / Q000187:drug effects / Q000502:physiology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D006168:Guinea Pigs; D006624:Hippocampus / Q000187:drug effects*; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000502:physiology
chemical_list: D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D015763:2-Amino-5-phosphonovalerate