Extracellular K+, Microflow and NAD/NADH Changes in Focal Cerebral Ischemia in Cats
The interrelationship of electrical function of the brain, the extra-cellular K+, NADH fluorescence and microflow was studied in acute focal cerebral ischemia in cats. The electrical activity, extracellular potassium (K+ e) changes and fluororeflectometry (NAD/NADH redox state and microflow) were measured in the middle ectosylvian gyrus in closed skull animals. The middle cerebral artery was clamped for two hours, and the observation was followed four additional hours after the release of the occlusion. The animals were classified into three distinct groups based on electrophysiological criteria. The severe stroked animals showed more than 80% reduction in the ratio of the electrical activity of the occluded territory to that on the contralateral side. In the moderate group the ECoG ratio was between 0.2–0.7 and if the ratio was over 0.7, the animals were classified as mild.
KeywordsMiddle Cerebral Artery Middle Cerebral Artery Occlusion Focal Cerebral Ischemia Mean Transit Time Extracellular Potassium
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