Neonatal hypoxia–ischemia reduces ganglioside, phospholipid and cholesterol contents in the rat hippocampus

Abstract

Hypoxia–ischemia is a common cause of neonatal brain damage producing serious impact on cerebral maturation. This report demonstrates that rats submitted to hypoxia–ischemia present a marked decrease in hippocampal gangliosides, phospholipids and cholesterol contents as from 7 days after the injury. Although chromatographic profiles of the different ganglioside species (GM1, GD1a, GD1b, and GT1b) from the hippocampus of hypoxic-ischemic hippocampi groups (HI) were apparently unaffected, as compared with controls, there were quantitative absolute reductions in HI. The phospholipid patterns were altered in HI as from the 14th to the 30th day after the injury, where phosphatidylcholine (PC) quantities were higher than phosphatidylethanolamine (PE); additionally, the cardiolipin band was detected only in hippocampi of control adult rats. In general, the absolute quantities of phospholipids were lower in HI than in correspondent controls since 7th day after the injury. Considering that reported effects were maintained, we suggest they express a late biochemical response triggered by the neonatal hypoxic-ischemic episode; the consequences would be cell death and a delay on brain development, expressed by a reduction on synaptogenesis and myelinogenesis processes.