[The expression of Fas after fluid percussion brain injury in rats]

To inquire into the pathologic diagnosis and the dating of injuries of light closed encephalon injury.

Wistar rats were hurt by fluid percussion, and were killed respectively at 15 min, 30 min, 1 h, 3 h, 6 h, 12 h, 1 d, 4 d, 7 d, and 14 d after injury. The expression of Fas in the cerebral cortex, thalamus, and hippocampi was detected by immunohistochemistry and the results were assessed by image analysis system.

The results showed that the expression of Fas could be detected in thirty minutes after injury, and then it increased significantly in three hours, reached apex in twelve hours after injury, decreased gradually in four days after injury, and returned to normal in 14 days after injury.

This research demonstrated that Fas-mediated apoptosis appeared not only around brain trauma but also in the brain tissue far away from the traumatic area. It indicted that Fas expression is a useful target for diagnosis of early brain injury and the regularity of Fas expression could be used as one of indications in deducing the time of brain injury.