Objective: To study the changes of expression of relevant factors in rat brain after concussion injury and to provide scientific basis for forensic estimation of brain injury interval.
Methods: Brain tissues were sampled from the established SD rat animal model of brain concussion, routinely processed and stained with HE and immunohistochemically stained with antibodies directed against heat shock protein 70 (HSP70), transforming growth factor beta 1 (TGF-beta1) and basic fibroblast growth factor (bFGF). The sections were examined under light microscope with IMAGE analytical system and homologous statistical analysis.
Results: The expression of HSP 70 was observed in 30 minutes after brain injury. The amount of neurons expressing HSP 70 increased gradually, reached its peak at 12 hours and then declined at 24 hours after brain injury. The expression of bFGF was observed 3 hours after injury in brain stem, reached its peak at 12 hours, and then declined. The expression of TGF-beta1 was detected 6-24 hours after brain injury, remained at its peak up to 3 days.
Conclusion: Brain injury can induce a chronological expression of HSP70, bFGF and TGF-beta1. The results can be a potential for estimating the age of brain injury using several markers.