超声生物显微镜评价高脂饮食促进载脂蛋白E基因敲除小鼠动脉粥样硬化

Assessment of atherosclerosis in ApoE knockout mice feeding with western diet using ultrasound biomicroscopy

目的 探讨应用超声生物显微镜（UBM）评价高脂饮食下载脂蛋白E（ApoE）基因敲除小鼠动脉粥样硬化的价值.方法 将32只8周龄ApoE基因敲除小鼠分为两组,一组饲以高脂饲料为高脂组,另一组饲以常规饲料作为对照组.饲养8周和16周后,采用Vevo 770超声成像系统观察两组小鼠升主动脉内-中膜厚度（IMT）及动脉粥样硬化斑块面积,并与病理组织学结果和血脂水平进行比较.结果 UBM显示高脂组和对照组小鼠主动脉根部管壁均增厚,出现粥样硬化斑块,但高脂组IMT及斑块面积均较对照组小鼠高,差异具有统计学意义（P＜0.05）.UBM所测IMT及斑块面积与病理结果相关性良好（r分别为0.81和0.70）；高脂组小鼠血清甘油三酯（TC）及总胆固醇（TG）水平均较对照组升高（P＜0.05）,UBM所测IMT随TC水平升高而增加,两者呈正相关（r=0.528）.结论 高脂饮食可促进ApoE基敲除小鼠主动脉粥样硬化斑块形成,超声生物显微镜能作为无创性观测手段来评价活体小鼠的动脉粥样硬化改变.

Objective To evaluate the value of ultrasound biomicroscopy （UBM） in assessment of atherosclerosis in apolipoprotein E （ApoE） knockout mice feeding with western diet.Methods Sixteen ApoE knockout mice in 8 weeks age were selected,then divided into two groups.One group was fed with west diet as high-fat group,and another group was fed with normal diet as control group.Intima-media thickness （IMT） and plaque area in the aortic root were assessed by UBM in two groups after 8 weeks and 16 weeks.And the measurements of UBM were compared with results of histopathology and blood-fat.Results Thicken wall and plaque could be find in aortic root in control group and high-fat diet group byUBM.IMT and plaque area in high-fat diet group was significantly higher than those of control group （ P 〈 0.05）.The IMT and plaque area in UBM were good correlation with histopathology （ rwas 0.81 and 0.70 respectively）.The triglyceride（TC） and total cholesterol in high-fat diet group was significantly higher than those of control group （ P 〈0.05）,and IMT in UBM were increased with the elevated level of TC,there was a positive correlation between IMT and TC（ r =0.528）.Conclusions Western diet can accelerate the process in formation of atherosclerotic plaque in ApoE knockout mice.UBM can be used to observe this prograss noninvasively in vivo mice.