| Traumatic brain injury (TBI) has been the threaten to human health and life, which with the high mortality and morbidity. With the acceleration of the procession of modernization, increased traffic, construction, sports injuries, accidents, natural disasters and other factors increasing, the medical profession has aroused widespread concern in society. TBI there has been a proliferation of power against a prominent question, and a serious social problem. TBI has made significant headway, With the raising level of scientific research and medical, traumatic brain injury in the rescue and treatment, the high morbidity of its incidence is still the troubled, important neurosurgerial issue. The study of brain injury-related changes in brain tissue has become a hot field of neurosurgery. TBI, the basis of theory, clinical treatment, drug development research is an important issue of neurosurgery.In this study, by the immunohistochemical methods, at different time points after injury lesions and the surrounding nerve tissue, we use TBI animal model in this research in order to find the changes of protein nestin, PSD-95, SYP, and the cell morphology electron microscopy ultrastructural changes; then observation of calcium channel changes by patch clamp technique to explore its significance and mechanism of the relationship between the TBI, to provide valuable theoretical basis of nerve regeneration, repair mechanism and clinical treatment. We divided the experimental application of adult SD rats into control group, sham-operated group, injury group which with the different damage to the hydraulic shock group, the pressure produced by different light, moderate and severe brain injury, and the collection of samples of 6h, 12h, 1d, 3d, 7d, 14d after injury. After using immunohistochemistry to detect rat frontal cortex, hippocampus CA1 region ,expression of nestin protein PSD-95, SYP then patch clamp technique on rat brain injury after calcium channel change, we use variance analysis and results of q test for statistical analysisthe same way, also we use electron microscopy to find the rat brain injury after morphological changes.Results:â‘ mild, moderate and severe injury group and nestin SYP immunoreactive protein expression were significantly higher than the same timeof the control group, sham-operated group, the difference was significant (p<0.05). severe injury group were higher than mild injury group, the difference was significant (p<0.05). severe injury group were also higher than that of moderate injury group, there was no significant difference (p> 0.05). In the severe group frontal cortex were higher than in hippocampal CA1 region, the difference was significant (p<0.05). mild injury group frontal cortex were higher than in hippocampal CA1 region, there was no significant difference (p> 0.05).â‘¡The expression of PSD-95 of severe injury group in immune activity was significantly lower than the control group at the same time,also lower than the sham group, the difference was significant (p<0.05). mild injury group was lower than the control group, the sham group, there was no significant difference (p>0.05); moderate injury group, severe injury group were lower than the mild injury group, the difference was significant (p<0.05). Severe injury group was lower than moderate injury group, the difference was significant (p<0.05), mild, moderate, severe injury group in frontal cortex were higher than those in hippocampal CA1 region. There was no significant difference (p> 0.05).â‘¢electron microscopy change: In the early time nucleus increased after pyknosis, nuclear dissolved. Mitochondrial swelling, and changing have been occurred after mitochondrial cavitation. Rough endoplasmic reticulum expansion, swelling, degranulation phenomenon also have been occurred after vacuolar changes. The dense air from the cytoplasm was same to the kind of changes.â‘£TBI calcium channel study finds that severe injury group at 6h, in the frontal cortex and hippocampus CA1 region, began to shows increasing of calcium channel of open probability and average opening time,then at 12h,increased significantly. The increasing will occur until 24h. But the average closing time decreased at 12h significantly, until 24h. In severe injury group open probability, the average opening times, the average closing time at 6h, contrast control group, sham-operated group, mild injury group were significantly different (p<0.05).The impact of TBI hydraulic model is simple, reproducible, maneuverable. and also the preferred model. We can varify different degrees of injury and different time of window for our research.In recent years the relationship between nestin protein and brain injury and rehabilitation has on the eye-catching way. After primary post-traumatic brain injury, the main pathological changes of neurons is apoptosis and necrosis. The expression of nestin is close to the repairing of nervous system. After damage, brain tissue can express a variety of substances, nerve cells may go into the embryonic stage of the downturn, then we can find nestin expression was significantly increased. Therefore nestin expression can be activated astrocytes as a sensitive indicator of brain damage,we can find it at the infer the time. The expression nestin was positively correlated with the injury, the more serious the injury, the expression increased significantly. Time Distribution: Injury 6h, 12h the expression increased, then the peak will be occurred at 7d, the expression declines at 14d. So we can say nestin protein is the early damage brain tissue markers in TBI. PSD-95 is the controversial and hot pot in neurosurgery research. PSD-95, the signaling molecules, linking the various central nervous system to the other, will be in favour of these signaling molecules in neurons of cluster and position, as the control neurons nerve signals in the immune response of the nervous system repairing and regeneration, PSD-95 has its special biological effects. In this study, in severe injury, immune activity of PSD-95 weakened at 6h, minimum time at 7d, then at 14d PSD-95 increase. mild injury group begin to decline at 12h, then 7d begun to rise. After the TBI, PSD-95may be related to cognitive dysfunction.SYP, a sign of a specific protein in synaptic vesicles ,found in the presynaptic nerve terminals components, is close to the synaptic plasticity. The immune activity of SYP in the mature brain tissue is highly concentrated in the presynaptic axon terminals, the surrounding neurons and their dendritic. SYP is one of the important symbols of synaptic reconstruction, and play an important role in rehabilitation. SYP of the injury group began to increase at 12h, the peak will beoccured at 7d, then at 14d, The expression of SYP declined. The expression of SYP has been an important brain tissue repair indicator after the TBI.Electron microscopy can accuratly and clearly record the ultrastructural changes of cell. This study showed that in the early time after TBI, nucleus increased after pyknosis, nuclear dissolved. Then after mitochondrial cavitation mitochondrial swell and change,. After vacuolar changes ,rough endoplasmic reticulum has ocured expansional, swelling, degranulational phenomenon. The dense air from the cytoplasm was same to the kind of changes. TBI showed changes in nerve cell damage, the more serious the injury, the more obvious changes.Patch-clamp technique is recorded by the ionic current ion channel to reflect a single ion channel activities of the technical elements on the membrane, also the methods to monito the ion channel patch on the ionic current. Calcium ions play a key role in the signal transduction afte r traumatic brain injury. Monitoring the changes in calcium ion channels afte TBI can help the pathogenesis of traumatic brain injury and clinical therapeutic research. In this study, the patch-clamp technique records the increasing of calcium open probability and the average opening times and reducing of average closing time. So we can confirme after TBI, nerve cells calcium has been overloaded. We can find less reporting on domestic about the dynamic observation of calcium distribution after TBI with varying degrees of injury and time window changes.In this study, in severe injury, Po, To increased from 6h to 24h. Tc significantly reduced. The time earlier after TBI calcium overload, the heavier degree occured. TBI is the early application of calcium antagonists, provide some theoretical basis and will be helpful to the clinical treatment.
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