| Objective: On the level of molecular biology, certain theoretical bases are provided for clinical therapy on the basis of deeply studying mechanism of delayed neuronal death after traumatic brain injury and probing into the influences of cognitive functions of CTP on rats after brain trauma.Methods: 1. The model of severe closed traumatic brain injury(TBI) was established according to the method created by Marmarou in 1994. 2. 300 Wistar rats were divided randomly into TBI group (n=96), CTP treating group (n=96) and fake operation group (n=96) and each of these three groups was divided into 8 subgroups, namely, 3, 6, 12, 24, 48, 72, 168 and 336 hours. At the same time, the rest 12 rats were taked as the normal group for comparison. 3. Medication: The CTP treating group after injury were treated with CTP (30mg/kg/d) in peritoneum; TBI group, the fake operation group and the normal group were treated with Saline for comparison at the same time and all were killed at each time point. 4. Another 48 rats were divided randomlyinto 4 groups, namely, brain injury group, CTP treating group, fake operation group and the normal group, and their cognitive dysfuction was evaluated using the Morris water maze(MWM). 5. Adopt such methods as H&E, immuno-histochemistry, TUNEL stain and Morris water maze dynamically observe pathological changes in hippocampus of rats and the expressions of p53, Bax and Fas proteins and space learning and memorizing changes after brain injury. 6. Through comparing neuronal apoptosis in hippocampus of each group at the same time point after injury, the expressions of p53, Bax and Fas proteins and the change characteristics of learning and memorizing functions, the influences of CTP on learning and memorizing obstructions of rats after injury are probed into.Results: 1. At 72 hours postinjury, the comprehensive neuronal degeneration and necrosis could be observed in the CA2-3 region of hippocampus, which tend to slow down as time went on. 2. Apoptosis-positive cells began to occur at 24 hours postinjury and its number increased with the time went on and in 7days postinjury the number came to the maximum and then it began to decline. Apoptosis-positive cells lied mainly in the CA2-3 region and dentate gyrus of hippocampus. In the CA2-3 region of hippocampus, apoptosis-positive cells were not detected in the fake operation group at every time point and the normal group. 3. P53 protein expression appeared in the CA2-3 region ofhippocampus in rats at 3 hours postinjury, strengthened obviously 12 hours later, reached maximum after a day or two, and declined 3 days later. After 7 days, the immune reaction of p53 proteins could not be detected, and positive cells were brown-yellow under microscope. In the CA2-3 region of hippocampus, positive cells were not detected in the fake operation group at every time point and in the normal group. 4. Immune reaction of Bax proteins strengthened in the region of CA2-3 in hippocampus in rats at 6 hours postinjury, reached maximum after 2 days or three, declined obviously 7 days later, and restored to the normal level on the 14th day. Slight immune reactions of Bax proteins could be observed in the Ca2-3 region of hippocampus of the normal group, while no obvious difference existed between the fake operation group at every time point and the normal group. 5. Fas protein expression strengthened in the CA2-3 region of hippocampus in rats at 6 hours postinjury, which became obvious 12 hours later, reached maximum after two days or three, and declined obviously 7 days later. Immune reactions of Fas proteins disappeared on the 14th day. Fas protein expression could not be detected in the C2-3 region of hippocampus in the fake operation group at every time point and in the normal group. 6. In comparison with TBI group, the apex of the expressions of P53, Bax and Fas proteins of neurons in hippocampus of CTP treating group declined obviously and apoptosis-positive cells also declined. 7. Morris water maze tests showed that obvious space learning and memor... |
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