Abstract: Objective To investigate the dynamics of the induction of S100β in different parts of rat brain following the diffuse brain injury. Methods Immunohistochemistry and auto-image analysis were to determine the expression of astroglial S100?茁 after diffuse brain injury in rats. Forty rats were distributed into groups according to injury time of 30 min, and 2,4,12,24 h, and 3,6 d after diffuse brain injury, and normal rats as control. Results The number of S100β positive cells in the four areas increased significantly followed by a decrease, and then a further increase. The expression of S100β could be detected increasing in 2h, and increased significantly in 4h, and it reached apex 12h after DBI, and decreased gradually to the level less than normal 3d, and returned to normal 7d following injury. In the postmortem injury groups, there were no significant changes in anti-S100β immunoreactivities in four areas of brain compared to the control group. Conclusion The present study showed the time-dependent expression of S100β is obvious following diffuse brain injury, and suggested S100β be suitable as a marker for brain injury age determination.

Key words: S100β, diffuse brain injury, injury age, immunohistochemistry