关键词: 长爪沙鼠, 弥散张量成像, 大脑, 衰老

Abstract: Objective　To observe trends in brain structural changes with increasing age in Mongolian gerbils using medical imaging techniques.Methods　A Bruker Pharma Scan 7.0T MRI scanner was employed to acquire whole-brain T2-weighted structural images and diffusion tensor imaging (DTI) data of the corpus callosum, hippocampus, amygdala, striatum, sensory cortex, and motor cortex in Mongolian gerbils aged 3, 12, 18, and 26 months (6-7 animals per group, both sexes included). Fractional anisotropy (FA) and mean diffusivity (MD) values were calculated from the DTI data.Results 1)FA values: compared with corpus callosum (0.47±0.08), left hippocampus (0.14±0.02), right hippocampus (0.13±0.03) in the 3 months group, the 18 months group showed significantly increase in the corpus callosum (0.62±0.07), left hippocampus (0.19±0.04), right hippocampus (0.18±0.02) (P<0.05). The 12 months group exhibited significantly increase in the right amygdala (0.21±0.03) (P<0.05). 2)MD values: compared with corpus callosum (8.15×10-4±5.43×10-5)/(mm2 /s), left hippocampus (7.53×10-4±2.32×10-5)/(mm2 /s), right hippocampus (7.35×10-4±4.55×10-5)/ (mm2 /s) in the 3 months group, the 18 months group demonstrated significantly decrease in the corpus callosum (6.41×10-4±6.51×10-5)/(mm2 /s), left hippocampus (6.52×10-4±2.08×10-5)/(mm2 /s), right hippocampus (6.54×10-4±3.25×10-5)/(mm2 /s)(P<0.05).Conclusion　The findings indicate that age-related structural changes in different brain regions of the Mongolian gerbil are asynchronous. However, an overall trend of initial increase followed by decline was observed. The period of structural maturation in the brain appears to occur between 12 and 18 months of age.

Key words: Gerbillinae, diffusion tensor imaging, brain, aging