Cerebral energy metabolism during hypoxia-ischemia correlates with brain damage: a 31P NMR study in unanesthetized immature rats.

The association between the ultimate brain damage resulting from unilateral hypoxic-ischemic insult (HI) and the changes in high-energy metabolites, measured by noninvasive phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy during the insult, was evaluated in 7-day postnatal rats. When the NMR metabolite levels were integrated over the last 1.5 h out of 2.5 h of HI, there was a significant correlation of both the estimator of phosphorylation potential (P < 0.001) and ATP levels (P < 0.01) with histologic score of damage and area morphometry. In particular, the development of cerebral infarction could be predicted from the NMR evaluation (P < 0.005). These findings suggest that a large disturbance in cellular energy metabolism is a prerequisite for the subsequent neuropathological alterations in this model.