Inhibition of TNF-alpha can attenuate or exacerbate excitotoxic injury in neonatal rat brain.

Tumor necrosis factor (TNF)-alpha, a multifunctional pro-inflammatory cytokine, has been implicated in the pathogenesis of acute ischemic brain injury. Recent data also suggest that TNF-alpha is a clinically relevant mediator of neonatal brain injury. We hypothesized that inhibition of TNF-alpha activity would reduce excitotoxic brain injury in neonatal rats. To test this hypothesis, we evaluated the efficacy of a TNF binding protein (bp) in attenuating NMDA-induced injury in 7 day old rats. Intrastriatal co-injection of TNFbp (3.75 microg) with NMDA (10 nmol) reduced striatal injury by 26%; in contrast, intra-hippocampal co-injection of TNFbp (3.75 microg) with NMDA (10 nmol) increased hippocampal damage by 68%. These findings indicate that TNF-alpha may have both beneficial and deleterious effects in the injured neonatal brain.