LOCAL CHANGES IN OXYGEN-TENSION AND BLOOD-FLOW IN THE BRAIN UNDER HYPERTHERMIA-INDUCED BY INTRACEREBROVENTRICULAR NMDA IN RATS

Intracerebroventricular administration of N-methyl-D-aspartate (NMDA; 100 nmol) to rats increased oxygen tension and blood flow of the cauda te putamen and the ventral hippocampus. The regional differences in th e increase in oxygen tension could not be explained in terms of those in the blood flow. NMDA also increased the temperature of the two brai n regions to a similar extent, and these increases preceded that in th e rectum. These findings suggest that NMDA receptor stimulation leads to exposure of the brain to a higher oxygen level and higher temperatu re, which might be involved in NMDA neurotoxicity.