Protection of CA1 pyramidal cell function by MK-801 following ischaemia in the gerbil.

Electrophysiological recordings were made from hippocampal slices of gerbils which had undergone a 5 min period of bilateral carotid occlusion. Normal CA1 population spikes, field potentials and synaptic responses were obtained from slices of gerbils pretreated with the N-methyl-D-aspartate antagonist, MK-801 (10 mg/kg, i.p., 1 h before the occlusion). In contrast, no CA1 population spike could be obtained from slices of untreated gerbils, although field potentials and population spikes were obtained from the dentate granule cell region of these slices in response to perforant path stimulation. These studies indicate that the CA1 pyramidal cells identified histologically as protected by MK-801 from selective neuronal degeneration produced by a 5 min period of global ischaemia, are also functionally protected and retain their normal synaptic responsiveness.