Regional Alterations in Glucose Consumption and Metabolite Levels during Postischemic Recovery in Cat Brain

Local CMRgl (LCMRgl) and metabolite levels were measured in the same tissue samples following 4 h of recirculation after 1 h of occlusion of the middle cerebral artery in the cat. The rate of glucose utilization was calculated using direct measurement of tissue deoxyglucose-6-phosphate and using a “lumped” constant corrected in each sample for alterations in tissue glucose. Increased LCMRgl (compared with that in sham-operated animals) occurred in regions with only minor alterations in levels of lactate and phosphocreatine. By contrast, LCMRgl was markedly depressed in regions with major changes in lactate and high-energy phosphates. Interestingly, tissue levels of glucose and unphosphorylated deoxyglucose were abnormally elevated in regions with profound energy failure. These results indicate an inhibition of glucose utilization in regions damaged by ischemia, despite the persistent elevation of tissue lactate. Increased glucose metabolism at 4 h post ischemia was detected only in areas with minor anaerobic alteration of metabolite levels.