The Expression Of GAP-43 And P38 In Rats Central Neuvous System After Traumatic Brain Injury

Traumatic Brain Injury (TBI) which always remain severe sequelae is the most frequently death cause of Central Nervous System diseases. Growth-associated protein-43 (GAP-43) and synaptophysin (p38) have an intimate relation with both of regeneration and development of neuron and synapse. And it will produce a marked effect in the regeneration after TBI. To have a promising therapy, it's important to identify their change regular pattern and to control the expression of both of them after TBI.Objective: To explore the change pattern of Growth-associated protein-43 (GAP-43) and synaptophysin (p38) in rats'CNS after TBI. For the purpose of providing the experiment basis for the further study of neuron regeneration and clinical therapy in traumatic brain injury.Methods: 125 adult maleness Sprague-Dawley (SD) rats were distributed to normal control group (5), sham control group (30) and injury group (90). The rats in injury group were made into brain injury model in the way of fluid percussion brain injury with different pressure (100kPa, 200kPa, 300kPa). Then brains of rats were collected at different time (6h,12h,24h,3d,1w,2w) and were fixed, embedded and sliced, then we determined the change of GAP-43 and p38 in tissues,samples of frontal cortex and CA1 district in cornu- ammonis by immunohistochemistry. All datas were observed by IPP image analytical system, then analysised statistically with variance analysis and q test.Results:1. Pathological changeDifferent degree damage in different areas of brain were seen in each group. Some of neurocytes in cortex and hippocampus change into arch form. And lots of akaryocytes diffuse in brain tissue. More necrosis neurocytes emerged in the brain cortex of injury side. Fewer neurocytes were seen in hippocampus. No evident change in normal control group and sham control group.2. Change of GAP-432.1 Reinforcement of GAP-43 immunocompetence emerged at the time of 12h after TBI, evident enhancement appeared 3 days later, the peak were reached at the time of 1w and the descent came after 2 weeks.2.2 12 hours after TBI, the CIOD figures of GAP-43 in injury group were significant higher than that in normal control group and sham control group, and had statistically significant differences (P<0.05). Comparison among low-grade injury group, mid-grade injury group and high-grade injury group: the CIOD figures of mid-grade injury group and high-grade injury group were significant higher than that in low-grade injury group, and had statistically significant differences (P<0.05). the CIOD figures of high-grade injury group were higher than that in mid-grade injury group, but no statistically significant differences appeared (p>0.05).3. Change of p383.1 Reinforcement of p38 immunocompetence emerged at the time of 24h after TBI, evident enhancement appeared 3 days later, the peak were reached at the time of 1w and the descent came after 2 weeks.3.2 24 hours after TBI, the CIOD figures of p38 in injury group were significant higher than that in normal control group and sham control group, and had statistically significant differences (P<0.05). Comparison among low-grade injury group, mid-grade injury group and high-grade injury group: the CIOD figures of mid-grade injury group and high-grade injury group were significant higher than that in low-grade injury group, and had statistically significant differences (P<0.05). the CIOD figures of high-grade injury group were higher than that in mid-grade injury group, but no statistically significant differences appeared (p>0.05).Conclusions:1. Diffuse hemorrhage and neurocyte necrosis were seen at the areas beyond injury part after TBI.2. The expression of GAP-43 and p38 enhance evidently in the areas of cortex and hippocampus CA1.3. Reinforcement of GAP-43 immunocompetence emerged at the time of 12h after TBI, evident enhancement appeared 3 days later, the peak were reached at the time of 1w and the descent came after 2 weeks.4. Reinforcement of p38 immunocompetence emerged at the time of 24h after TBI, evident enhancement appeared 3 days later, the peak were reached at the time of 1w and the descent came after 2 weeks.5. The increasing degree of immunocompetence of GAP-43 and p38 is more evident when injury is more serious.