Research On Multiple Concussions Rat’s Balance, Perceive, Depressive Behavioral, Molecular Imaging Changes, Tau Protein And Aβ1-40 Of Brain Tissue Changes

[Objectives]:To establish the pure cerebral concussion(PCC) rat model and multiple cerebral concussion(MCC) rat model which strike them every 24h, Observe the PCCs 2MCC.4MCC rat’s beam balance(BB) test、beam walking(BW) test、morris water maze(MWM) test、forced swimming(FS) test behavior changes, Assess the rats’ homeostasis movement, the restoration of learning and memorizing, the depression status of mental activity. [Methods]:(1) animal grouping:64 healthy SD male rats, weighing 260±20g, the rats were randomly distributed into N group(normal group)、 PCC group、2MCC group and 4MCC group, the execute time to each of these groups was randomly divided into 2 weeks(2w) and 3 months(3m) after concussion. (2) The rats were duplicated in batcher with metal pendulum device and each group of PCC、 2MCC and 4MCC had 16 rats. After the duplication, the rats were randomly and evenly distributed into every experimental group including 2w-PCC group、2w-2MCC group、2w-4MCC group、3m-PCC group、3m-2MCC group、3m-4MCC group; N groups was distributed into 2w-N group and 3m-N group. (3) The BB test and BW test were used to assess the changes of rats’static and dynamic balance function、 dynamic coordination function、learning and memorizing function in PCC group、 2MCC group and 4MCC group; The MWM test were used to assess the recovery of rats’learning and memorizing function in PCC group、2MCC group and 4MCC group; The FS test were used to assess the rats’depression after concussion in PCC group、2MCC group and 4MCC group. The results of each group were compared.[Results]:(1) The results of BB evaluation:the result of rats in PCC group and 2MCC group was 60.00±0.00s, which in static balance all the time; the rats in 4MCC group appeared different degree of damage of static balance function, and the time increase of survival period after injury could exacerbates the damage. (2) The results of BW evaluation:the rats in PCC group restored to normal after the first day of injury, i.e the score remains in 5 throughout the experiment. The rats been tested in the noise stimulus can successfully run through the obstacles in the rod and into the cartridge. The 4MCC rats’BW score decreased in 1-2 days after injury, the 4MCC and N groups、the PCC and 2MCC groups were statistically significant, P<0.05, and then back to 5. (3) The results of BW slip into incubation period:compared 4MCC group with N group and PCC group,1-5 days after injury were statistically significant, P<0.05; compared 2MCC group with N group,2-7 days after injury were statistically significant, P<0.05. compared 3m-4MCC group with 2w-4MCC group、3m-2MCC group with 2w-2MCC group、3 m-PCC group with 2w-PCC group、3m-N group with 2w-N group, were statistically significant in 1-7days after injury, P<0.05. (4) MWM test:① In the experiment of underwater platform:The escape latent period trend of N group、PCC group、2MCC group and 4MCC group declined rapidly in 1-2 days after injury and declined slowly in 3-7 days after injury. Compared with N group:the escape latent period of 4MCC group、2MCC group and PCC group were statistically significant in 1-5 days after injury, P<0.05; Compared with PCC group:the escape latent period of 4MCC group and 2MCC group were statistically significant in 2-5 days after injury, P< 0.05. compared 3m-4MCC group with 2w-4MCC group.. 3m-2MCC group with 2w-2MCC group、3m-PCC group with 2w-PCC group、3m-N group with 2w-N group, were statistically significant in 1-5days after injury, P<0.05. ② In the experiment of above water platform:the escape latent period of N group were lower than other groups, P<0.05; compared with PCC group:the escape latent period of 4MCC group and 2MCC group were statistically significant in 1-2 days after injury, P<0.05; compared with 2MCC group:the escape latent period of 4MCC group were statistically significant in 1-2 days after injury, P<0.05. compared 3m-4MCC group with 2w-4MCC group、3m-2MCC group with 2w-2MCC group、 3m-PCC group with 2w-PCC group、3m-N group with 2w-N group, were statistically significant in 1-2days after injury, P<0.05.③ In the experiment of no water platform: the standing time at first quadrant of rats in every group were significantly more than other three quadrants, the standing time at first quadrant:N group> PCC group> 2MCC group> 4MCC group, the difference was statistically significant, P< 0.05; compared with PCC group:the differences of 4MCC group and 2MCC group were statistically significant, P< 0.05; compared with 2MCC group:the differences of 4MCC group were statistically significant, P<0.05. compared 3m-4MCC group with 2w-4MCC group、3m-2MCC group with 2w-2MCC group、3m-PCC group with 2w-PCC group、3m-N group with 2w-N group, the differences of standing time at first quadrant were statistically significant, P<0.05. (5) The frequency of the depression status in FST:compared 4MCC group and 2MCC group with PCC group and N group, the differences of 1 day and 2 day after injury were statistically significant when executed at 2w, P< 0.05; only the differences of 2 day after injury to 2MCC group and PCC group were statistically significant when executed at 3m, P< 0.05; compared 4MCC group with PCC group, the differences of 1 day and 2 day after injury were statistically significant, P<0.05; compared 2MCC group with PCC group, the differences of 2 day after injury were statistically significant, P< 0.05; compared 4MCC group with 2MCC group, only the differences of 7 day after injury were statistically significant when executed at 2w, P< 0.05, and the differences of 1 day and 2 day after injury were statistically significant when executed at 3m, P< 0.05; compared 3m-4MCC group with 2w-4MCC group、3m-2MCC group with 2w-2MCC group、3m-PCC group with 2w-PCC group、3m-N group with 2w-N group, the differences of 1 day and 7 day after injury were statistically significant, P<0.05. The most common behavior of 4MCC group was the C behavior. [Conclusions]:(1) There were no injury changes of static balance function existing to the rats in PCC group and 2MCC group; there were injury changes of static balance function existing to the rats in 4MCC group. (2) The dynamic balance function, dynamic coordination function、learning and memorizing function of rats in PCC group and 2MCC group changed shortly after the last striking, while the functions of rats in 4MCC group signally changed all the time after injury. (3) The injury of dynamic balance function dynamic coordination function. learning and memorizing function of rats became worse with the extension of rats’survival time. (4) The more times rats be striked, the more depressive behavior of rats acted, and the depressive behavior aggravated with the extension of rats’survival time.[Objectivesl:Do magnetic resonance spectrum(MRS) and diffusion tensor imaging (DTI) to the PCC,2MCC,4MCC rats which are 2 weeks(2w) and 3 months(3m) after concussion, and analysis the results. [Methods]:Apply the American Signa HDxt 3.0T superconducting magnetic resonance imaging and Special animal coil, the rats were put on the special animal coil after anesthesia and placed in an MRI scan bed to do the MRS and DTI. [Results]:(1)The results of MRS:① In the prefrontal cortex coronal section, the hippocampus coronal section and the brainstem sagittal cross-sectional areas of the brain, the NAA、NAA/Cho、NAA/Cho of PCC group、2MCC group and 4MCC group showed significantly decrease; the Cr showed mildly decrease; the Cho and Cho/Cr showed significantly increase; the MI and LL showed mildly increase.② Compared the 4MCC group with the N group, the NAA、 NAA/Cho、NAA/Cho、Cho、Cho/Cr、MI、LL were statistically significant, P<0.05; compared the 2MCC group with the N group, the NAA、NAA/Cho、NAA/Cho、 Cho、 Cho/Cr、MI、LL were statistically significant, P<0.05; compared the PCC group with the N group, the NAA、NAA/Cho、 NAA/Cho、Cho、Cho/Cr were statistically significant, P<0.05; Compared the 4MCC group with the PCC group, the NAA, NAA/Cho、NAA/Cho、Cho、Cho/Cr、MI、LL were statistically significant, P<0.05; compared the 2MCC group with the PCC group, the NAA. NAA/Cho、NAA/Cho、 Cho、Cho/Cr were statistically significant, P<0.05; compared the 4MCC group with the 2MCC group, the NAA、NAA/Cho、NAA/Cho、Cho、Cho/Cr、MI、LL were statistically significant, P<0.05.③ Compared the 3m-N group with the 2w-N group、 3m-PCC group with 2w-PCC group、3m-2MCC group with 2w-2MCC group、 3m-4MCC group with 2w-4MCC group, the NAA、 NAA/Cho、NAA/Cho、Cho、 Cho/Cr、MI、Cr were statistically significant, P<0.05. (2)The results of DTI: ① in the prefrontal cortex coronal section, the hippocampus coronal section and the brainstem sagittal cross-sectional areas of the brain, the FA and RA of the PCC group、2MCC group and 4MCC group showed significantly decrease; the ADC and VR showed significantly increase.② Compared the 4MCC group with the N group、 the 2MCC group with the N group, the PCC group with the N group、the 4MCC group with the PCC group、the 2MCC group with the PCC group、the 4MCC group with the 2MCC group, the FA、RA、ADC、VR were statistically significant, P< 0.05.③Compared the 3m-N group with the 2w-N group、3m-PCC group with 2w-PCC group、3m-2MCC group with 2w-2MCC group、3m-4MCC group with 2w-4MCC group, the FA、RA、ADC、VR were statistically significant, P<0.05.[Conclusions]:(1)The multiple concussions rat’s imaging changes can be detected by MRS and DTI; (2)multiple concussions rat’s neurons was damaged, numbers of nerve cells reduced, glial cells proliferated, aerobic oxidation got hard, and the heavier was the damage, the more obvious was the change; (3) With the extension of rat’s survival time, multiple concussions rat’s neuron damaged, glial cells’ proliferation and aerobic oxidation got worse;(4) multiple concussions rat’s white matter fiber bundle was damaged and angioedema was showed, and got worse with the heavier of damage; (5)multiple concussions rat’s damage degree of white matter fiber bundle and degree of angioedema aggravated with the extension of rats’survival time.[Objectives]:To observe and all the experiment rats’group to be compared the expression changes of Aβ 1-40 and total Tau proteins changes in PCC,2MCC and 4MCC rats’brain tissue. To evaluate and compare the changes in optical density of Aβ 1-40 and total Tau proteins after the traumatic.[Methods]:Took cerebral perfusion for each group, using the anti Aβ 1-40 and the anti total Tau to conduct chemical dyeing and the Immunohistochemical S-P method dyeing, and detect the changes in optical density of the Aβ 1-40 and the total Tau expression in each coronary section, the hippocampus coronary section, and brain stem failure section of different brain regions were tested in using the image analysis system. [Results]:(1) The results of the anti total Tau immunohistochemistry:① In each part of the septum sections, compared the 4MCC group with the N group、compared the 2MCC group with the N group、compared the PCC group with the N group、compared the 4MCC group with the PCC group、compared the 2MCC group with the PCC group, compared the 4MCC group with the 2MCC group, the Tau optical density were statistically significant, P< 0.05; compared the 3m-N group with the 2w-N group、3m-PCC group with 2w-PCC group、3m-2MCC group with 2w-2MCC group、3m-4MCC group with 2w-4MCC group, the Tau optical density were statistically significant, P<0.05. ② In Pa, cc, Cal, Ca3, PoDG-S,3 VPe, RF and ic parts of the hippocampus sections, compared the 4MCC group with the N group、compared the 2MCC group with the N group、 compared the PCC group with the N group、compared the 4MCC group with the PCC group、compared the 2MCC group with the PCC group, compared the 4MCC group with the 2MCC group, the Tau optical density were statistically significant, P<0.05; compared the 3m-N group with the 2w-N group、3m-PCC group with 2w-PCC group、 3m-2MCC group with 2w-2MCC group、 3m-4MCC group with 2w-4MCC group, the Tau optical density were statistically significant, P<0.05. ③In tz, Gi and pyx parts of the brain stem sections, compared the 4MCC group with the N group、compared the 2MCC group with the N group、compared the PCC group with the N group、 compared the 4MCC group with the PCC group、compared the 2MCC group with the PCC group, compared the 4MCC group with the 2MCC group, the Tau optical density were statistically significant, P< 0.05; compared the 3m-N group with the 2w-N group、3m-PCC group with 2w-PCC group、3m-2MCC group with 2w-2MCC group、 3m-4MCC group with 2w-4MCC group, the Tau optical density were statistically significant, P< 0.05.(2) The results of the anti Aβ1-40 immunohistochemistry: ① In each part of the septum sections, compared the 4MCC group with the N group、 compared the 2MCC group with the N group、compared the PCC group with the N group、compared the 4MCC group with the PCC group、compared the 2MCC group with the PCC group, compared the 4MCC group with the 2MCC group, the Aβ 1-40 optical density were statistically significant, P<0.05; compared the 3m-N group with the 2w-N group、3m-PCC group with 2w-PCC group、3m-2MCC group with 2w-2MCC group、3m-4MCC group with 2w-4MCC group, the Aβ 1-40 optical density were statistically significant, P<0.05. ② In Pa, cc, Cal, Ca3, PoDG-S,3VPe, RF and ic parts of the hippocampus sections, compared the 4MCC group with the N group、compared the 2MCC group with the N group、compared the PCC group with the N group、compared the 4MCC group with the PCC group、 compared the 2MCC group with the PCC group, compared the 4MCC group with the 2MCC group, the Aβ 1-40 optical density were statistically significant, P<0.05; compared the 3m-N group with the 2w-N group、3m-PCC group with 2w-PCC group、3m-2MCC group with 2w-2MCC group、3m-4MCC group with 2w-4MCC group, the Aβ 1-40 optical density were statistically significant, P<0.05. ③ In tz, Gi and pyx parts of the brain stem sections, compared the 4MCC group with the N group、compared the 2MCC group with the N group、compared the PCC group with the N group、compared the 4MCC group with the PCC group、compared the 2MCC group with the PCC group, compared the 4MCC group with the 2MCC group, the Aβ 1-40 optical density were statistically significant, P<0.05; compared the 3m-N group with the 2w-N group、 3m-PCC group with 2w-PCC group、3m-2MCC group with 2w-2MCC group、 3m-4MCC group with 2w-4MCC group, the AP 1-40 optical density were statistically significant, P< 0.05. [Conclusions]:(1)The Tau positive optical density were expressed varying degrees of rise, and in this section, all were the highest expression of three months after the injury. Furthermore, the Tau positive expression was correlated positively with the degree of damage. (2)The Aβ 1-40 optical density were expressed varying degrees of rise, and in this section, all were the highest expression of three months after the injury. Furthermore, the Aβ 1-40 positive expression was correlated positively with the degree of damage. (3)The Tau and the Aβ1-40 play an important role in the occurrence of CTE progression. (4)Among the PCC,2MCC and 4MCC three types of damage extent, the 4MCC was the heaviest damage, and has the most obvious damage cumulative effect.