Establish A Standardized Model Of Spinal Cord Injury In Mice And Research On The Damage Mechanism In MiR- 31 Transgenic Mice

Objective:1.To standardize date of the spinal cord beating injury model in mice,two modles were established by comparing two kinds of spinal cord beating injury model instruments’ advantages in the experiments.2.To understand the recovery situation of spinal cord injury in mi R- 31 transgenic mice,and to further understand the mechanisms of the mi R- 31 control and improve the microcirculation of the spinal cord injury. Methods:Part one:40 mice were randomly divided into 2 groups with 10 mice in each group: homemade Allen spinal cord beating device group(Group A, n=20) and Impactor M-Ⅲ spinal cord contusion system group(Group B, n=20). The two groups were established by beating spinal cords in mice with these two equipments. The BBB motor function scores were respectively evaluated and recorded 1d, 3d, 5d, 7d, 14 d and 21 d after operation to evaluate the recovery situation of lower limbs in mice.And the spinal cord injury are dyed with HE in 3d, 7d, 14 d,21d.Part two : Using the Impactor M- III impactor Kunming mice(group A, n=30) and mi R-31 transgenic mice(group B, n=30). After the operation,using BBB score, H E staining, immunofluorescence and fluorescence quantitative PCR detection.in 3d, 7d, 14 d and 21 d. Results:Part one:The degree of recovery in two sets of SCI models in mice was slightly different 1d, 3d, 5d and 21 d after operation(p>0.05).The degree of recovery in Group B were apparently better than those in Group A at time nodes of 7d and 14 d after operation(p<0.05).And there is on different in morphology.Part two:Two different groups in the production of spinal cord injury model in mice after recovery trend is same, but there are still differences exist.The degree of recovery inGroup B were apparently better than those in Group A at time nodes of 7d and 14 d after operation(p<0.05).There is only a little deifferent in the form of organization in 14 d and 21 d.The ruslt of immunofluorescence staining and PCR:Two sets of results are basically the same in Nestin.It is different between two groups in NSE, the expression of group B is greater than the amount of group A. Conclusion:Part one:The mice SCI model can be successfully established by each of these two kinds of spinal cord beating experimental instruments. And the recovery situations in Group B were apparently faster and more stable than those in Group A.And Impactor M-Ⅲ can make an efficient pattern,standardize it and improve the sucess rate.Part two:mi R- 31 may play a improve role in the micro environment in spinal cord injury,and it can promote the recovery of spinal cord injury.