[Animal modeling]-MRI features of Aβ1-40 lateral ventricle injection to simulate Alzheimer

  Objective: To analyze the brain imaging characteristics of tree shrews in Alzheimer's disease (AD) models.

  Method: Inject Aβ1-40 into the upper cerebral ventricle of the stereotactic instrument to establish an AD animal model. After the visuospatial behavior test confirmed the success of the model, MRI was used for coronary artery T2-weighted imaging (T2WI) and diffusion tensor imaging (DTI) analysis.

  Results: The reference memory errors (3 weeks, 4 weeks) and working memory errors (2 weeks, 3 weeks, 4 weeks) of the model group were significantly higher than those of the control group (Pu003c0.05). ). The time for the model group to complete the task (2 weeks, 3 weeks) was significantly longer than that of the control group (Pu003c0.05). After 3 weeks, the tree shrews in the model group decreased in one or both hippocampus, and increased in the corresponding lateral or bilateral ventricles. After 12 weeks, the width of the bilateral temporal lobes of the tree shrews in the model group was significantly larger than that of the control and treatment groups (Pu003c0.01). Scanning of diffusion tensor images showed that the apparent diffusion coefficient (ACD) on both sides of the hippocampus of tree shrews in the model group was higher than that in the control group (Pu003c0.01). The corpus callosum fasciculation was severely damaged in the model group.

  Conclusion: Injecting Aβ1-40 into the lateral ventricle will cause the learning and memory of tree shrews to decrease. MRI can show the characteristic changes in AD Treeshrew's brain. Temporal lobe width, hippocampal ADC value and corpus callosum fiber damage are the criteria for diagnosing dementia.