ABSTRACT
OBJECTIVE@#To investigate Homer protein expression after focal brain contusion and explore the relationship between expression and injury time.@*METHODS@#Focal brain contusion in rats was established and Homer protein expression in brain at different injury intervals after contusion was detected by immunohistochemistry and Western blotting.@*RESULTS@#A small amount of Homer positive expression cells were detected in control group, sham operated group and experimental group (0.5 h after contusion). The amount of Homer positive expression cells increased after 3 h and reached peak 12 h after contusion. The amount of positive cells continued to decrease 1 d after contusion and to the base level 7 d after contusion. Homer protein expression based on immunohistochemistry and Western blotting had statistical difference among adjacent groups.@*CONCLUSION@#Expression of Homer protein near the focal contusion area shows time dependence after brain contusion in rats.
Subject(s)
Animals , Male , Rats , Blotting, Western , Brain/pathology , Brain Injuries/pathology , Carrier Proteins/metabolism , Contusions/pathology , Disease Models, Animal , Forensic Pathology , Homer Scaffolding Proteins , Immunohistochemistry , Random Allocation , Rats, Wistar , Staining and Labeling , Time FactorsABSTRACT
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.
Subject(s)
Animals , Male , Rats , Blotting, Western , Brain Injuries/enzymology , Forensic Pathology , Immunohistochemistry , Matrix Metalloproteinase 3/genetics , Random Allocation , Rats, Sprague-Dawley , Time FactorsABSTRACT
OBJECTIVE@#To establish a new animal model of grading skeletal muscle contusions that could be controllable and repetitive.@*METHODS@#The rats' gastrocnemius was injured by a new weight-dropping device designed. The force acting on gastrocnemius with a comparatively constant duration and inducing elastic deformation of the gastrocnemius was expressed with velocity (v) and deformation (DF). Instant velocity was changed to create gastrocnemius contusions. Pathological changes of gastrocnemius were graded by the gross and histological examinations of 39 rats.@*RESULTS@#At low level of impact (v: 2 m/s, DF: 5.5 mm), mild injuries were detected in epimysium and superficial layer of gastrocnemius. At moderate level of impact (v: 2.5 m/s, DF: 6.5 mm), the injuries were observed in epimysium and whole gastrocnemius. At high level of impact (v: 3 m/s, DF: 7.5 mm), severe injuries were seen deeper to soleus with more extensive skeletal muscle damage.@*CONCLUSION@#Grading of skeletal muscle blunt force contusion is created by parameter of velocity and muscle deformation. The model could be used for further research on skeletal muscle contusions.