[Animal modeling] - Analysis of magnetic resonance spectroscopy and ultrastructure in hippocampus of APP/PS1 double transgenic AD model mice

  Objective To observe the relationship between the changes of metabolites in the hippocampus of APP/PS1 transgenic mice and the ultrastructural pathological changes, so that the APP/PS1 transgenic mice can be better used in the experimental study of Alzheimer's disease (AD).

  Methods The learning and memory abilities of APP/PS1 transgenic mice and wild mice of the same age and background were compared by new object recognition experiment; The contents of N-acetyl aspartic acid (NAA), inositol (MI), choline (Cho) and glutamic acid (Glu) in hippocampus of the two groups were compared by 1HMRS; The ultrastructure of nerve cells and astrocytes was observed by transmission electron microscopy.

  Results Compared with wild mice, the ability of learning and memory of transgenic mice decreased, and the difference between the two groups was statistically significant (P<0.05); The ratio of NAA to creatine (Cr) in hippocampus decreased significantly (P<0.05), while the ratio of mI/Cr and Cho/Cr increased (P<0.05); Mitochondria of nerve cells and astrocytes degenerated and pyknotic, the number of secondary lysosomes increased, and astrocytes were overactivated and phagocytic to dystrophic synapses.

  Conclusion The changes of NAA, MI, Cho and other metabolites in hippocampus of APP/PS1 transgenic mice can reflect the process of AD lesions β- The abnormal inflammatory reaction induced by amyloid and the destruction of synaptic structure and other pathological characteristics provide experimental basis for better application of APP/PS1 gene mice in AD research.