Alteration of Bcl-2, Bcl-x and Bax protein expression following fluid per cussion brain injury in rats / 第二军医大学学报

ABSTRACT

Objective: To investigate the alteration of bcl- 2 gene family in the rat brain and the molecular mechanism of neuronal apoptosis following traumatic brain injury. Methods: Male Sprague -Dawley rats were subjected to lateral fluid percussion brain injury(FPI) of mo derate severity. Bcl-2, Bcl-x and Bax protein expression was detected by immun ohistochemistry. Results: (1) The immunoreactivity of Bcl-2 and Bcl-x protein decreased in the hippocampus ipsilateral impact site as early as 6 h post-injury, and this was the main cause of down-regulation of the ratio of Bcl-2+Bcl-x to Bax. (2) During 1-3 d after injury, the Bax protein express i on increased significantly, while the Bcl-2 and Bcl-x protein expression decre ased relatively slow. The decreased ratio of Bcl-2+Bcl-x to Bax was mainly due to the Bax up-regulation. Conclusion: The bcl-2 gene family is involved in neuronal apoptosis after FBI, and the protein expression alteration of the family members leads the neuronal cell to apoptosis.