Objective: To examine the role of polymorphonuclear neutrophils (PMNs) in early progressive injury of deep partial-thickness burn wound.
Methods: After deep partial-thickness burn, the count of PMNs in beripheral circulation, activity of myeloperoxidase (MPO) and content of MDA in wound tissue of Spraque Dawley rats, were measured. Sections of wound biopsies were stained with Masson's thrichromatic staining and anti-vimentin immunohistopathologic staining for identifying the injured tissue.
Results: PMNs counts increased immediately and reached a peak at 4 h postburn, and MPO activity peaked at 24 h postburn. MDA content was lowe at 0.5 h and higher at 48 h postburn than that of normal control. Histologic analysis showed that there was more necrotic tissue at 48 hr postburn than that at 24 h.
Conclusion: It was after 24 h postburn that PMNs induced tissue damage. The results suggest that intervention of PMNs adhesion should be under taken in about 4 h after thermal injury and anti-oxidizing agent should be given before 24 h postburn in order to prevent early progressive injury to the wound.