| Objective1. To establish a reliable model of the acute clip-type spinal cord injury in rats;2. To explain the effect of electro-acupuncture on the spinal cord injury and the differentiation of the endogenous neural stem cells;3. To research the expression of BMP-2in SCI after the electro-acupuncture treatment.4. To provide experimental basis for electro-acupuncture treatment of spinal cord injuryMethods:SD rats were randomly divided into the SCI group, the SHAM group and the EA group. Aneurysm-clipping(temporary) methods were used to make up an acute spinal cord injury model and draw materials on the1st,3rd,7th,14th,21st and28th day respectively after the injury. The reliability of the acute clip-type SCI model was evaluated through BBB score, SEP, MRI, pathological section. The neural function was assessed after EA treatment with the use of the BBB scores. After the DAB staining to frozen sections, the proliferations of OPCs, APCs, eNSCs and ASs in the spinal cord anterior horn were viewed and the expression of the BMP-2in the injured spinal cord tissue in each group observed by WB.Results:1. The Comparison of the BBB score data of the two groups vertically suggested that the data of the SHAM group were significantly higher than those of the SCI group. Each set of the data increased gradually with the prolongation of the postoperative time. There was significant difference as to the different time points within the same group (P<0.05) and the statistical comparison of the points at the same time between different groups was significant (P<0.05).2. SEP waveform of the SHAM group was normal, with the latency prolonged slightly after the operation, the wave amplitude being reduced slightly and then being back to normal. As to SEP of the SCI group, no waveform could be detected short term after the operation (<7days). The latency was longer and the amplitude was after7days. However, the latency would decrease slowly and the wave amplitude would increase gradually with time. In comparison, there was no statistical significance as to the latency and amplitude in each time point of the SHAM group (P>0.05) and there was also obviously statistical significance as to the latency and amplitude in each time point of the SCI group (P<0.05).3. MRI results:The injured region on the thoracic spinal cord showed a regional spot-like high T2WI signal6hrs after the operation, and with the swelling of the thoracic spinal cord, large areas of the injured region and caudal spinal cord presented high T2signal1-3days postoperatively. T2WI high signal area was narrowed7-14days after the operation and the T2WI high signal remained little and the diameter in distal spinal cord was reduced conspicuously21-28days after the operation. MRI of the SHAM group at various time points had no distinct change.4. Pathological findings of the HE staining:Such signs as the hemorrhage, the edema, the structural disorder and the disappearance of gray matter layer were found with the examination of the spinal cord6hrs and lday postoperatively and the neuron structure was damaged along with the nerve cell swelling and nuclear pyknosis3-7days postoperatively. However,7-14days after the operation, the edema in nerve cells began to be relieved along with the infiltration of inflammatory cells.21-28days postoperatively, the edema in nerve cells significantly was alleviated, inflammatory cells began to fade away. As a result, glial cells began to proliferate and the tissue structure of the SHAM group was clear.5. The electric-acupuncture treatment could obviously improve the BBB ethology score and higher scores could be gained with time.6. Compared to the other two groups at the same time, the number of eNSC in EA group was significantly higher and there was statistical significance between the different groups (P<0.05). The quantity of cells between the different time points in EA group increased gradually as the time of the treatment went on, indicating that there was statistical significance between the different time (P<0.05). 7. In comparison to the number of oligodendrocyte between the different groups at the same time, the number in EA group was significantly higher than that in the other two groups and there was statistical significance between the different groups (P<0.05). Also the amount of cells between the different time points in EA group increased gradually as the time of the treatment went on. The contrast between the different time points was significant statistically (P<0.05).8. Compared with the other two groups at the same time, the number of OPCs in EA group was significantly higher than that of the other two groups, which indicated that there was statistical significance between the different groups (P<0.05). In comparison between the different time points in EA group, the number of cells increased gradually as the time fo the treatment went on. The contrast between the different time points was significant statistically (P<0.05). Brdu positive cells and NG2positive cells were increased express with immunofluorescence in EA group (P <0.05).9. As contrasted with the other two groups at the same time, the number of astroglia in EA group was significantly lower and there was statistical significance between the different groups (P<0.05). Compared between different time points in EA group, the number of cells decreased gradually with the time going. The contrast between the different time points was significant statistically (P<0.05). Brdu positive cells and GFAP positive cells were decreased express with immunofluorescence in EA group (P <0.05).10.7-14days after the injury, the expression of BMP-2appeared obviously enhanced and by the time this high-level expression continued up to28days, the expression of BMP-2in the EA group was lower than that in the SCI group. The difference was highly significant statistically with the passage of time (P<0.05).Conclusion:1. It is simple to make the model of the acute clip-type spinal cord injury in rats and it is stable, can be used repeatedly and can be controlled2. Electric-acupuncture can significantly improve the BBB behavior score of rats in spinal cord injury and from the perspective of ethology it obviously has a therapeutic effect on the spinal cord injury. Electric-acupuncture could induce the proliferation and differentiation of eSCs,OLs and its precursor cells in the remote segment behind the injury point. Also, it could inhibit the proliferation and differentiation of astroglia in the remote segment behind the injury point.3. Electric-acupuncture might promote the functional recovery after the spinal cord injury by inhibiting the expression of BMP-2.4. Providing experimental basis for electro-acupuncture treatment of spinal cord injury... |
PDF Full Text Request