Effect of hypoxic-ischemic insults on the composition of fatty acids in the brain of neonatal rats.

Background: Long-chain polyunsaturated fatty acids, especially docosahexaenoic acid (DHA; 22:6 n-3), comprise a major component of brain membrane phospholipids. The effect of neonatal hypoxic-ischemic insults on brain fatty acid composition is not completely understood. The aim of this study was to investigate alterations in brain fatty acid composition during development and in response to hypoxic-ischemic insults in neonatal rats.

Methods: Postnatal day 7 pups were randomly assigned to two experimental groups: a control group or a hypoxic-ischemic group in which hypoxia-ischemia was produced by left common carotid artery occlusion and exposure to 8% oxygen for 1.5 h. Various brain fatty acids were measured on postnatal days 8, 10 and 14.

Results: On postnatal day 14, the ratio of DHA to total fatty acids increased in the control group, but not in the hypoxic-ischemic group (p < 0.05). We observed no significant differences in arachidonic acid content in the brain between the two groups.

Conclusions: These results suggest that hypoxic-ischemic insults interfere with accumulation of brain DHA in developing rats. DHA supplementation may be beneficial for treating neonatal hypoxic-ischemic encephalopathy.