Expression study of GFAP and VEGF in a closed craniocerebral injury model
Objective To investigate the expression pattern of GFAP and VEGF after closed brain injury in rats,and to infer the time elapsed after brain injury,and then to provide reference for the inference of injury time.Methods Male rats were randomly divided into control group and experimental group,in which the experimental group was divided into 1 h,6 h,12 h,1 d,3 d,7 d and 14 d groups according to the different elapsed time after injury.Immunohistochemistry and ELISA were used to detect the expression of GFAP and VEGF in brain tissue and serum of rats after closed brain injury.Results(1)In each immunohistochemistry experimental group,GFAP was mainly expressed in the cytoplasm of astrocytes,with an obvious increase at 1 h after injury,a progressive increase of expression in 7 d,and a decrease of expression close to the level of the control group at 14 d after injury.While VEGF was mainly expressed in the cytoplasm of neurons,with an obvious increase at 1 d after injury,a peak at 3 d post-injury,and a decrease in expression at 14 d.(2)In each ELISA experimental group,the VEGF content in serum of each experimental group increased earlier than the VEGF expression in brain tissue,which began to increase significantly at 6 h after injury,and the content was the most at 3 d after injury,and was close to that of the control group at 14 d after injury.Conclusion(1)It has showed temporal changes in the expression of GFAP and VEGF,and both are expected to be biological markers for inferring the time of injury in forensic work.(2)GFAP and VEGF have high sensitivity and specificity and are important for the extrapolation of early craniocerebral injury time.