Abstract: To observe the pathologic changes and the expression of nuclear factor-kappa B(NF-κB)after diffuse axonal injury(DAI) in rats,its mechanism is firstly explored.The rat DAI model was established.Immunohistochemical SABC method was used to observe the expression of NF-κB,combining Glees-Marsland and Weil staining to observe the pathologic changes in different stage of DAI.Swollen and ruptured axon were found in brain tissue 1 h after DAI,and myelin sheath showed edema,delamination,marked axonal retraction ball and screen shape changes were detected after 24 h,and those morphological changes reached the peak after 72 h.The expression of NF-κB could be detected 1h after injury,the positive cells increased after 3 h,peaked after 24 h,and kept this tendency for 72 h.The positive cells decreased after 7 d.The control group showed negative staining.The findings showed that the expression of NF-κB increased in rat DAI model.The NF-κB may play an important role in secondary axonal injury.

Key words: diffuse axonal injury, special staining, nuclear factor-kappa B(NF-&kappa, B), immunohistochemistry