摘要
目的采用二维斑点追踪成像技术观察单纯性肥胖大鼠左心室收缩功能变化。方法将16只健康雄性大鼠以普通饮食(NF组,n=6)和高脂饮食(HFD组,n=10)喂养12周,之后记录常规超声心动图参数,并采用二维斑点追踪技术分析大鼠左心室心肌应变和应变率,观察大鼠心肌纤维化、肥大细胞浸润程度及轻链3(LC3)蛋白表达水平。结果与NF组相比,HFD组大鼠体质量、腹围、腹部脂肪含量、空腹血糖及甘油三酯均显著增高(P均<0.05);左心室前间隔径向应变率及前间隔、前壁径向应变减低(P均<0.05),后间隔基底段、中间段、心尖段及侧壁基底段纵向应变及应变率均减低(P均<0.01)。HFD组大鼠心肌细胞排列紊乱,脂肪空泡,心肌胶原纤维沉积和肥大细胞浸润明显增加,LC3蛋白表达明显降低。结论肥胖大鼠早期心脏结构无明显改变时,已存在不同程度左心室功能受损。
Objective To evaluate left ventricular systolic function with two-dimensional speckle tracking imaging (2D- STI) in rats with simple obesity. Methods A total of 16 healthy male rats were fed with normal diet (NF group, n=6) and rich fat diet (group HFD, n= 10) for 12 weeks. The parameters of conventional echocardiography were recorded, and the strain and strain rate of left ventricular myocardium were analyzed with 2D-STI. The degree of myocardial fibrosis, mast cell infiltration and the expression level of light chain 3 (LC3) protein were observed. Results Compared with NF group, in HFD group, the weight, abdominal circumference, abdominal fat content, fasting blood glucose and triglyceride increased (all P〈0. 05), while the radial strain rate of anterior septum, the radial strain of anterior septum and anterior wall in left ventricular decreased (all P〈0.05), so did the longitudinal strain and strain rate in posterior septal basal segment, middle segment, apical segment and lateral wall basal segments in left ventricle (all P〈0. 01). In HFD group, the arrangement of cardiac muscle cells was disordered, and the fat vacuoles was found; the myocardial collagen fiber deposition and the infiltration of mast cells obviously increased, while the expression of LC3 protein decreased. Conclusion The left ventricular function of early stage obese rats has been damaged in varying degrees when no obvious changes of heart structure could be observed.
作者
曾丽琴
张军
拓胜军
王雅韵
胡运
贺建国
高宇
ZENG Liqin;ZHANG Jun;TUO Shengjun;WANG Yayun;HU Yun;HE Jianguo;GAO Yu(Department of Ultrasound, Xijing Hospital, the Air Force Military Medical University, Xi'an 710032, China;Military Preventive Medical College, the Air Force Military Medical University, Xi~an 710032, China)
出处
《中国医学影像技术》
CSCD
北大核心
2018年第4期481-485,共5页
Chinese Journal of Medical Imaging Technology
基金
国家自然科学基金(81271580).