[Role of p38 mitogen-activated protein kinase signal transduction pathway in the acute lung injury of severely burned rats].

Objective: To investigate the role of p38 mitogen-activated protein kinase (MAPK) signal transduction pathway in the acute lung injury of severely burned rats.

Methods: Forty-eight adult healthy rats were randomly divided into three groups: sham group, burn control group, and burn + SB203580 group. A third-degree burns over 30% total body surface area rat model was used and pulmonary capillary permeability, lung water content, pulmonary histology and p38 MAPK activity were measured at 24 hours postburn.

Results: Burn trauma resulted in increased pulmonary capillary leakage permeability (42.5 +/- 4.7 vs. 12.1 +/- 1.4, P < 0.01), elevated lung water content (P < 0.05), and worsen histologic condition. There was a significant activation of p38 MAPK at 24 hours postburn compared with control. SB203580 inhibited the activation of p38 MAPK, reduced the pulmonary capillary leakage permeability (24.7 +/- 2.9 vs. 42.5 +/- 4.7, P < 0.01), decreased lung water content, and prevented burn-mediated lung injury.

Conclusion: The activation of p38 MAPK is one important aspect of the signaling event that contributes to burn-induced lung injury.