Effects of a novel NMDA receptor antagonist on experimental stroke quantitatively assessed by spectral EEG and...

We used spectral electroencephalographic (EEG) analysis to demonstrate the physiological effect of focal brain ischaemia induced by permanent occlusion of the right middle cerebral artery in rats. A significant shift to lower frequency EEG activity occurred relative to the baseline power spectrum within one hour following the occlusion. Spectral EEG analysis also revealed a cerebroprotective effect of a noncompetitive N-methyl-D-aspartate receptor antagonist, CNS 1102, administered 15 min post-occlusion. Animals treated with this NMDA antagonist exhibited only 26.5% of the slowing in the ischaemic hemisphere compared to animals given a placebo. Post-mortem analysis conducted 24 h later also revealed reduced infarction volumes for the treated animals, there was a highly significant correlation between the extent of spectral EEG slowing during the initial development of the infarction and subsequent lesion size. These results suggest that spectral EEG analysis may be useful in the early evaluation of experimental and perhaps human stroke and for monitoring the effects of cerebroprotective therapies.