Jianing Yue1, Li Yin2, Jian Shen3, Zhenjie Liu4. 1. Department of Vascular Surgery, Zhongshan Hospital, Fudan University, Shanghai, China. 2. Department of Vascular Surgery, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China. 3. Department of Cardiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China. 4. Department of Vascular Surgery, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China. Electronic address: lawson4001@zju.edu.cn.
Abstract
OBJECTIVE: To establish a murine abdominal aortic aneurysm rupture model using a combination of elastase treatment and angiotensin II infusion. METHODS: The murine abdominal aorta was treated with elastase. Angiotensin II was infused at a dose of 1000 ng/kg/min via an osmotic pump placed subcutaneously. A saline osmotic pump was used as the control. The aortas were harvested from the mice 4 weeks later, or earlier if mice died. The abdominal aorta was inspected using ultrasound and microscopy for aneurysm formation and/or signs of rupture. The aneurysm outcome was measured using aortic expansion and proinflammatory cytokine expression. It was also compared with the established conventional elastase perfusion and angiotensin II infusion abdominal aortic aneurysm models. RESULTS: By day 28 after surgery, all abdominal aortas of mice treated in the modified group had dilated and progressed to abdominal aortic aneurysms with 60% ruptured aneurysms, whereas none of the control aortas treated with saline became aneurysmal. In mice treated with elastase solution alone, 100% developed aneurysms and only one had a ruptured aneurysm. In mice given angiotensin II infusion alone, 37.5% developed aneurysms and none had a ruptured aneurysm. Histological examination of the modified murine abdominal aortic aneurysm rupture model was identical to those observed in the conventional elastase model. Quantitative polymerase chain reaction analysis revealed similarly increased levels of proinflammatory cytokines. CONCLUSIONS: We modified two current murine abdominal aortic aneurysm models to develop a murine abdominal aortic aneurysm model with consistent aneurysm formation and high rupture incidence, which can be used for studying abdominal aortic aneurysm rupture and treatment.
OBJECTIVE: To establish a murineabdominal aortic aneurysm rupture model using a combination of elastase treatment and angiotensin II infusion. METHODS: The murine abdominal aorta was treated with elastase. Angiotensin II was infused at a dose of 1000 ng/kg/min via an osmotic pump placed subcutaneously. A saline osmotic pump was used as the control. The aortas were harvested from the mice 4 weeks later, or earlier if mice died. The abdominal aorta was inspected using ultrasound and microscopy for aneurysm formation and/or signs of rupture. The aneurysm outcome was measured using aortic expansion and proinflammatory cytokine expression. It was also compared with the established conventional elastase perfusion and angiotensin II infusion abdominal aortic aneurysm models. RESULTS: By day 28 after surgery, all abdominal aortas of mice treated in the modified group had dilated and progressed to abdominal aortic aneurysms with 60% ruptured aneurysms, whereas none of the control aortas treated with saline became aneurysmal. In mice treated with elastase solution alone, 100% developed aneurysms and only one had a ruptured aneurysm. In mice given angiotensin II infusion alone, 37.5% developed aneurysms and none had a ruptured aneurysm. Histological examination of the modified murineabdominal aortic aneurysm rupture model was identical to those observed in the conventional elastase model. Quantitative polymerase chain reaction analysis revealed similarly increased levels of proinflammatory cytokines. CONCLUSIONS: We modified two current murineabdominal aortic aneurysm models to develop a murineabdominal aortic aneurysm model with consistent aneurysm formation and high rupture incidence, which can be used for studying abdominal aortic aneurysm rupture and treatment.