Expression of matrix metalloproteinase-3 after brain contusion in rats / 法医学杂志

OBJECTIVE@#To investigate the expression of matrix metalloproteinase-3 after brain contusion and its applicability for estimating the age of brain contusion.@*METHODS@#Rats had been divided into three groups: control group, sham operation group and brain contusion group. The expression of matrix metalloproteinase-3 at different time was detected by immunohistochemistry and Western blot.@*RESULTS@#By the immunohistochemistry, no staining was observed in control and sham operation groups. The positive staining of MMP-3 appeared 6 hours after contusion, increased gradually in 24 hours and peaked 5 days after contusion, then started to decrease, 14 days after contusion still could be observed. By the Western blot analysis, no expression of MMP-3 was detected in control and sham groups. The positive staining of MMP-3 appeared 6 hours after contusion, increased gradually and maximized 5 days after contusion, then started to decrease, 14 days after contusion still could be found.@*CONCLUSION@#Time-order expression of MMP-3 could be used for estimating the age of brain contusion in forensic pathology.

The dynamically changes of COX-2 and the gene expression of COX-2 mRNA after traumatic brain injury in rats / 法医学杂志

OBJECTIVE@#To illuminate the pathology of traumatic brain injury(TBI) and to better understand the relationship between the expression of COX-2 and the time course of TBI.@*METHODS@#Immunocytochemical staining, double-labeled with the anti-COX-2 antibody and either the neuron-specific antibody NeuN or the astroglial-specific marker GFAP, in situ hybridization and computer image analysis were used.@*RESULTS@#Results from immunohistochemistry indicated time-dependent staining changes of neuronal plasma. The immunostained cells were faint at control cortex, mostly were neurons. The immunostained cells appeared to be darkly stained 30 min after TBI for extended periods of time and reached the maximum at 2 d after injury, reached another peak (P < 0.05) at 4 d post-injury. The darker cells persisted in a high level, significant differences (P < 0.05) even presented between control and 15 d post-injury. The COX-2 mRNA expression was faint at control cortex. The expressions of COX-2 mRNA appeared to be darkly stained 15 min after TBI for extended periods of time and reached the maximum (P < 0.05) at 1 d post-injury, reached another peak (P < 0.05) at 3 d post-injury, and significant differences (P < 0.05) even presented between control and 7 d post-injury, but not 15 d post-injury.@*CONCLUSION@#The results of this study indicated that the expression of COX-2 mRNA and protein had a possible relationship with the extended periods of time after TBI. It might have some relationship between the expression of COX-2 and secondary brain injury after TBI.