Abstract:Objective To study the changes of liver, aortic wall and heart function in hyperlipidemia hamster at different time points via ultrasonic imaging, and investigate the value of ultrasonic diagnosis in hamster model of hyperlipidemia. Methods 32 Syrian Golden hamsters were randomly divided into two groups that were fed with normal chow (control group) and high fat diet (model group) respectively. Serum lipids levels were analyzed after 0, 3, 6, 9, 14, 16, 20, 24, 40 weeks using commercial kits. Hamsters from each group were examined with ultrasound and then sacrificed for pathological examination in the 20th week and 40th week. Results Serum levels of TC, TG, HDL-C and LDL-C increased remarkably in hamsters fed with high fat diet and maintained significantly above the normal levels throughout the study course (p<0.05). Compared with the control group, hamsters fed with high fat diet for 20 weeks had greater internal-media thickness (IMT) (p<0.0001) and their IMT increased significantly when the dietary intervention period was extended to 40 weeks (p<0.0001). It was revealed by both ultrasonic imaging and pathological examination that fatty liver and aortic arch atherosclerotic lesions were developed in hyperlipidemia hamsters fed with the high fat diet for 20 weeks, and aggravated during the prolonged 20 weeks. Conclusion IMT of aortic arch walls of hamster can be dynamically measured through ultrasonic imaging. It can also be used to monitor liver and sensitively detect the morphological changes of aortic arch walls of hyperlipidemia hamster.

Abstract:ObjectiveTo compare the difference of two heart failure models established by constriction of aortic arch and abdominal aorta, and to explore an effective method to establish an animal model of heart failure. MethodsNinety healthy adult male Wistar rats were randomly divided into three groups. The rats in the group 1 had cervical operation to contract the aortic arch, the rats in the group 2 were operated on abdomen to contract the abdominal aorta, and the rats in the group C had surgery but no aorta constriction. All the rats were fed for 4 or 6 weeks. The heart function of the rats was detected with ultrasound and heart intubation. ResultsAt 4 weeks after constriction, ultrasonic results showed a significant increase of the left ventricular wall thickness and internal diameter of the left ventriclular cavity in the aortic arch constriction group, and not significantly increased in the abdominal aorta constriction group, compared with those of the control group. At 6 weeks after constriction, both the left ventriclular wall thickness and internal diameter of the left ventricle were significantly increased in the abdominal aorta constriction group, while only the internal diameter of the left ventricle was significantly increased and without change of the left ventriclular wall thickmess in the aortic arch constriction group. Hemodynamic detection showed that LVESP, LVEDP, LVDP and ±dp/dtmax in the aortic arch constriction group were significantly lower than those of the abdominal aorta constriction group at 6 weeks after contraction. ConclusionThe progression of heart failure caused by aortic arch constriction in the rats occurs obviously faster than that developed after abdominal aorta constricction.