Neurochemical Research

, Volume 16, Issue 3, pp 279–284 | Cite as

Anoxic block of GABAergic IPSPs

  • K. Krnjević
  • Y. Z. Xu
  • L. Zhang
Original Articles


In rat hippocampal slices GABAergic IPSPs are very rapidly suppressed by anoxia (in<2 min). Both early (GABAA) and late (GABAB) components are affected. After reoxygenation, the IPSPs recover, but only slowly and not always completely. Iontophoretic applications of GABA or baclofen indicated no major depression of responses during anoxia. It is therefore unlikely that the anoxic suppression of IPSPs is caused by desensitizations of GABA receptors. A more probable explanation is a failure of GABAergic neurons to release GABA from inhibitory nerve terminals.

Key Words

Anoxia inhibitory synaptic potentials (IPSP) GABA baclofen hippocampus 


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Copyright information

© Plenum Publishing Corporation 1991

Authors and Affiliations

  • K. Krnjević
    • 1
    • 2
  • Y. Z. Xu
    • 3
  • L. Zhang
    • 4
  1. 1.Anaesthesia Research DepartmentMcGill UniversityMontréalCanada
  2. 2.McIntyre Centre for Medical SciencesMontréalCanada
  3. 3.Department of BiologyUniversity of Science and Technology, of ChinaHefeiChina
  4. 4.Playfair Neuroscience UnitToronto Western HospitalToronto

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