Abstract
Our previous study together with other investigations have reported that neonatal hypoxia or ischemia induces long-term cognitive impairment, at least in part through brain inflammation and hypomyelination. However, the detailed mechanisms are not fully understood. Here, we used a rodent model of neonatal hypoxia by subjecting postnatal day 0 (P0) rat pups to systemic hypoxia (3.5 h). We found that neonatal hypoxia increased the glutamate content and initiated inflammatory responses at 4 h and 1 day after hypoxia, caused hypomyelination in the corpus callosum, and impaired hippocampus-dependent learning and memory when assessed 30-60 days after hypoxia. Interestingly, much of the hypoxia-induced brain damage was ameliorated by treatment with the ATP analogue 2',3'-0-(2,4,6-trinitrophenyl)-adenosine 5'-triphosphate (TNP-ATP; blocks all ionotropic P2X1-7 receptors), whereas treatment with pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS; inhibits P2X1-3 and P2X5-7 receptors) was less neuroprotective. Our data indicated that activation of ionotropic ATP receptors might be partially, if not fully, involved in glutamate deregulation, neuroinflammation, hypomyelination, and cognitive dysfunction after neonatal hypoxia.