Abstract: Objective To investigate the expressions of phospho-p38MAPK(p-p38MAPK) during the incised wound healing of the skin in mice and to explore the applicability of the time-dependent expressions of p-p38MAPK in the determination of wound age. Methods The expression of p-p38MAPK in incised skin wound was detected by immunohistochemistry and Western blot. Results There was a minimal baseline expression of p-p38MAPK in control mouse skin. Expression of p-p38MAPK was mainly detectable in neutrophils in the wound specimens from 3 hours to 12 hours after injury. Afterwards,the p-p38MAPK positive cells were mostly mononuclear cells and fibroblasts between post-injury day 1 and day 5,whereas the p-p38MAPK positive cells were mostly fibroblasts between post-injury day 7 and day 14. Morphometrically,the ratio of the p-p38MAPK positive cells to total number of the cells increased gradually in the wound specimens aged from 3 hours to 12 hours,and maximized in the wound specimens aged 12 hours with a slight decrease at 24 hours after injury. The ratio maintained at high level from post-injury day 3 to day 5,and then decreased gradually from post-injury day 7 to day 14. The expression of p-p38MAPK was observed throughout the wound healing stages by Western blot as well with a peak expression occurring between 12 hour and day 3 after injury. Conclusion Our data suggest that p-p38MAPK may play an important role in inducing apoptosis of neutrophils,mononuclear cells,and fibroblasts during skin wound healing and meanwhile,p-p38MAPK may be a potentially useful marker for wound age determination.

Key words: forensic pathology, skin wound, apoptosis, p-p38MAPK, wound age determination