RESUMO
Glutamate excitotoxicity is among the main cellular mechanisms leading to perinatal insults in human newborns. We used intracerebral injection of the glutamatergic glutamate N-methyl-D-aspartate-receptor agonist ibotenate to produce excitotoxic lesions mimicking the acquired white matter lesions seen in human preterm infants. We evaluated whether nonsteroidal antiinflammatory drugs (NSAIDs) protected against glutamate excitotoxicity. Aspirin (0.01-100 microg/d), indomethacin (0.1-10 microg/d), paracetamol (10-100 microg/d), or NS-398 (12.5 microg/d) was given daily before ibotenate (P1 to P5) or after ibotenate (P5 to P9). Lesion size was measured on Cresyl Violet-stained brain sections collected on P10. None of the drugs tested alone or in combination increased lesion size. Pretreatment with low- or high-dose aspirin and post-treatment with paracetamol or NS-398 protected against white matter lesions, whereas cortical lesions were decreased by pretreatment with low- or high-dose aspirin or post-treatment with NS-398. The corticosteroid betamethasone (0.18 microg/d) was neuroprotective when given before or after ibotenate and this effect was reversed by concomitant aspirin therapy (10 microg/d). In conclusion, perinatal NSAID administration may have beneficial effects on brain injury if appropriately timed.