In vitro study on bFGF expression of rat astrocytes after mechanical injury / 法医学杂志

OBJECTIVE@#To study the alteration of basic fibroblast growth factor (bFGB) expression in astrocytes in vitro after mechanical injury and to understand the repair mechanism of brain injury.@*METHODS@#Astrocytes were isolated from cerebral cortex of SD rats born in 24 hours, and then cultured and purified. The cultured astrocytes were randomly divided into control group and injury groups that were subjected to mechanical injury at 30 min, 1h, 3h, 6h, 12h, 24h, 3d, and 7d. The levels of bFGF expression in the astrocytes after injury were detected by ABC immunohistochemistry.@*RESULTS@#More than 95% of the cultured cells were astrocytes. The levels of bFGF expression werevery low in the control group. On the other hand, increased levels of bFGF expression could be observed at 1-3h after injury. The expression levels increased significantly at 6-12h, reached peak level at 24h, remained at the high level up to 3 days, and the decreased gradually.@*CONCLUSION@#The changes of bFGF expression levels in cultured astrocytes in vitro after mechanical injury are similar to that observed in vivo experimental model, both of which show time-dependant characteristic, with only slightly earlier expression of bFGF observed in vitro. Thus, the expression of bFGF after injury can be one of evidences for estimation of brain injury intervals. the cell injury model in vitro may have superiority in the study of the molecule mechanism of tissue and cell injury.

Changes of HSP70, bFGF and TGF-beta1 expression in rat brain after concussion / 法医学杂志

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.