中文摘要：

目的应用3.0 T ^1H-MRS技术探讨血管性认知障碍（vascular cognitive impairment,VCI）大鼠脑内代谢物浓度的纵向变化及其在早期诊断中的潜在价值。材料与方法利用Philips 3.0 T MR扫描仪和小动物线圈对血管性认知障碍大鼠（术后2周、1个月、3个月、5个月）进行^1H-MRS扫描,并结合Morris水迷宫和HE染色、Nissle染色评估VCI大鼠认知障碍及海马的病理变化。结果与对照组相比,术后2周,VCI大鼠即出现明显的学习记忆能力障碍,大鼠脑内（主要包括海马）的代谢物Glu/tCr显著下降（P=0.029）;术后1个月,NAA/tCr显著下降（P=0.027）,而mI/tCr显著上升（P=0.005）;术后3个月,NAA/tCr含量有所恢复,mI/tCr（P=0.007）显著上升,而GPC/tCr,t Cho/tCr含量显著上升（P值均〈0.05）;术后5个月,除mI/tCr仍保持在较高水平（P=0.039）外,其他代谢物均恢复至正常水平;HE和Nissle染色显示海马区域存在细胞结构和形态的改变。结论 3.0 T ^1H-MRS技术提供的代谢物含量客观地反应了VCI进展中大鼠脑内代谢物浓度的改变,VCI大鼠在术后2周即出现Glu/tCr比值的下降以及VCI进程中表现出来的mI/tCr持续升高可能有助于早期提示VCI的诊断。

英文摘要：

Objective： To explore the application of 3.0 T ^1H-MRS in assessment of longitudinal changes of brain metabolites in vascular cognitive impairment（VCI） rats and its potential value in early diagnosis of VCI disease. Materials and Methods： Philips 3.0 T MR scanner combined with animal coil were applied to obtain ^1H-MRS data of brain（mainly including the hippocampus） in VCI rats at different time points（2 weeks, 1 month, 3 months and 5 months）, Morris Water maze test and pathologic examination（HE and Nissle staining） were also performed to evaluate the cognitive impairment and pathological changes. Results： Compared with controls, at 2 weeks, significantly cognitive impairment and deduction of Glu/tCr ratio（P0.05）were found. And reduction of NAA/tCr（P0.05） and increasing of mI/tCr（P0.05） were detected at 1 month, at 3 months, the increase of mI/tCr were kept, and also GPC/tCr（P0.05） and t Cho/tCr（P0.05） were raised, at 5 months, all metabolites recovered to normal level besides mI/tCr. But, HE and Nissle stainings showed that cell structural and morphological changes can also exist in the hippocampus. Conclusions： The abnormal metabolites provided by 3.0 T ^1H-MRS maybe can reflect the pathological changes in progression of VCI, objectively. Results from this study suggested that reduction of Glu/tCr at the onset and sustained rise of mI/tCr in the progress of VCI, can be helpful for diagnosis of VCI at its early stage.