扩散张量成像评价2型糖尿病兔模型认知功能相关脑区白质微结构变化

目的 探讨2型糖尿病(T2DM)对认知功能相关脑区白质微结构的损伤以及病程对损伤程度的影响。方法 雄性日本大耳白兔30只,随机选取24只建立T2DM模型(模型组),余6只为对照组;于建模后12、16、20和24周行DTI,测量额叶白质、前扣带回、胼胝体膝部、胼胝体压部及后扣带回ADC和FA值。结果 与对照组比较,模型组建模12周时各部位ADC值和FA值无统计学差异(P均>0.05),16周起后扣带回、胼胝体膝部、胼胝体压部ADC值开始增高、FA值开始降低(P均<0.05),20周起额叶白质、前扣带回ADC值亦开始增高、FA值开始降低(P均<0.05);随T2DM病程延长,ADC值逐渐增高、FA值逐渐降低。结论 T2DM兔模型的认知相关脑区白质微结构受损,其损伤程度随病程延长而加重,前部白质损伤晚于后部白质。

Diffusion tensor imaging in assessment of microstructure changes of white matter related to cognitive function in rabbit models of type 2 diabetes mellitus

Objective To explore the microstructure injures of white matter (WM) related to cognitive function induced by type 2 diabetes mellitus (T2DM) and the impact of disease duration on injury degrees. Methods Totally 30 male Japanese big-ear rabbits were randomly divided into T2DM group (n=24) and control group (n=6). On the 12th, 16th, 20th and 24th week after establishment of T2DM model, DTI was performed to measure ADC and FA of frontal lobe (FL), anterior cingulum (AC), posterior cingulum (PC), genu of corpus callosum (CC) and splenium of CC. Results Compared with control group, ADC and FA had no obvious changes in T2DM group on the 12th week (all P>0.05). PC, genu of CC and splenium of CC showed raise of ADC and reduction of FA (all P<0.05) from the 16th week, FL and AC also showed the same changes (all P<0.05) from the 20th week in T2DM group. ADC increased and FA decreased gradually along with the duration of disease course. Conclusion In rabbit models of T2DM, WM microstructure were injured related to cognitive function, and the injury degree was associated with the disease duration.