Microglial apoptosis is a "key" in the central nervous system after traumatic brain injury, which followed by many change in brain and body.The mechanism and temporal and spatial pattern of microglial apoptosis is not been well known. The purpose of this research project was to investigate the temporal and mechanism of microglial apoptosis after traumatic brain injury.According to the purpose of our study and the experimental condition available, rat after traumatic brain injury by machinery dash was determined to be the animal model in vivo. On the base, we processed researchs in four parts. The research included:1. Making a block of tissue microarray of 56 rat brains from lh to 30d after traumatic brain injury,and optimize some conditions to improve this "young technique" .2. Examining expressions of both apoptosis and some factors related with apoptosis in microglial on tissue microarray and the whole sections by several methods-HE,TUNEL, DAPI, immunohistochemical, double-label under fluorescence.3. On the basis of the results of TMA and relative reports,cell apoptosis model N9 induced by excellular ATP was built to mimic traumatic brain injury in vitro. As same as the model in vivo ,we examined the expressions of both apoptosis and some factors related with apoptosis in microglial with same methods:HE,DAPI, TUNEL, transmission electron microscope ,immunohistochemical, double-label under fluorescence method.4. Using PF-2D,we screened and identified the different proteome between normal and theapoptosis cell stimulated by ATP. Our conclutions are:1 The results got from TMA were nearly concided with that from traditional whole sections.TMA is an effective technology which could be used in histology.2 Identified 12 proteins from the different proteome between normal and apoptosis microglial.3 Among the total 12 proteins,ll proteins are never documented in the reports of apoptosis,which may be "new family member in apoptosis" .