Objective: After injecting different concentrations of amyloid Aβ25-35 into the cerebral ventricle, observe the changes in the learning and memory ability of the Morris water maze in rats, and determine the best Aβ25-35 injection concentration for AD model rats.
Method: Male SD rats were randomly divided into sham operation group and model group. The injection concentrations of Aβ25-35 in the model group were 2, 4 and 8μg/μL, respectively. Refer to the "stereotactic map of rat brain", select the right ventricle and inject aggregated Aβ25-35 to prepare an AD rat model. Seven days after the successful modeling, the Morris water maze was used to test the changes in learning and memory abilities of each group of rats.
Result: Comparing the average swimming speed, there is no significant difference between rats in each group (P \u003c0.05). The results of escape latency showed that compared with the sham operation group, the escape latency of rats in the model group was significantly longer, and the difference was statistically significant (P0.05). Compared with the sham operation group, the target quadrant activity time and distance of rats injected with different doses of Aβ25-35 in the model group were significantly reduced, and the difference was statistically significant. The results show that it exists (P0.05). The results of the space exploration show that compared with the sham operation group, the number of injections of different doses of Aβ25-35 on the entire platform of the rats in the model group was significantly reduced, and the difference was statistically significant (significant difference). P0.05).
Conclusion: When the Aβ25-35 protein is injected into the cerebral ventricle unilaterally to prepare a rat AD model, the recommended injection concentration of Aβ25-35 is 4μg/μL.