Kinetics of polymorphonuclear neutrophil infiltration after a traumatic brain injury in rat.

THE aim of our study was to assess polymorphonuclear neutrophil infiltration into the injured parenchyma after a traumatic brain injury (TBI). Myeloperoxidase (MPO) activity was assayed on the hippocampus, temporal and parietal cortex 6, 24, 48, 72, and 120h post-trauma. MPO activity occurred in these structures from 6h post-trauma and was maximum at 24-48 h. It was resolved by 72h in the hippocampus and the parietal cortex, but persisted in t e temporal cortex until 120h after trauma. This suggests that neutrophil infiltration is a delayed phenomenon in the physiopathology of TBI. Considering that a large therapeutic window may be crucial in the management o TBI, inhibition of neutrophil infiltration needs to be further investigated following cerebral trauma.