Background: Impaired energy metabolism during HI may induce apoptosis. This could have implications for neural rescue therapies.

Subjects and Interventions: Apoptotic and necrotic cells were counted in the cingulate gyrus in 8 newborn piglets subjected to transient HI while observed by magnetic resonance spectroscopy, and 5 controls.

Results: 48 hours after HI mean 11.9% (SD 6.7%) of cells were apoptotic and 11.4% (8.4%) necrotic, while in controls 4.1% (2.7%) were apoptotic and 0.7% (1.3%) necrotic. Apoptotic and necrotic cell counts were related to: (1) the decline in the ratio of nucleotide triphosphates to the exchangeable phosphate pool during HI; (2) the fall in the ratio of phosphocreatine to inorganic phosphate 8-48 hours after HI; and (3) an increased ratio of lactate to total creatine at both these times.(p<0.05).

Conclusion: Apoptosis is related to impairment of energy metabolism following transient HI.