Angiotensin II Infusion in apoE Wild-type Mice
Objective: To determine whether angiotensin II infusion alone can generate aneurysms in apoE wild-type mice, and to establish that hyperlipidemia is required for aneurysm formation when combined with angiotensin II
Protocol Steps
Osmotic minipump implantation
Implant osmotic minipumps containing either angiotensin II or vehicle control into mature apoE wild-type mice
Note: Pumps deliver continuous infusion over the entire month-long experimental period
View evidence from paper
“we infused Ang II or vehicle for 1 month via osmotic minipumps into mature apoE +/+ mice”
Measurement of arterial blood pressure
Monitor arterial blood pressure throughout the infusion period to assess hemodynamic effects
Note: These doses of Ang II did not alter arterial blood pressure in apoE+/+ mice
View evidence from paper
“These doses of Ang II did not alter arterial blood pressure, body weight, serum cholesterol concentrations”
Body weight monitoring
Track body weight changes throughout the infusion period
Note: Ang II infusion did not alter body weight in apoE+/+ mice
View evidence from paper
“These doses of Ang II did not alter arterial blood pressure, body weight, serum cholesterol concentrations”
Serum cholesterol measurement
Measure serum cholesterol concentrations and distribution of lipoprotein cholesterol
Note: Ang II did not alter serum cholesterol or lipoprotein cholesterol distribution in apoE+/+ mice
View evidence from paper
“These doses of Ang II did not alter arterial blood pressure, body weight, serum cholesterol concentrations, or distribution of lipoprotein cholesterol”
Tissue collection and examination
Collect aortic tissue and examine for atherosclerotic lesions and aneurysms
Note: Examine for presence or absence of abdominal aortic aneurysms and atherosclerotic lesions
View evidence from paper
“infusions of Ang II into apoE +/+ mice failed to generate aneurysms”
Sequential sectioning of aortic tissue
Perform sequential sectioning of abdominal aorta to characterize any structural changes
Note: Examine for medial breaks, adventitial remodeling, and dilation
View evidence from paper
“Sequential sectioning of aneurysmal abdominal aorta revealed two major characteristics: an intact artery that is surrounded by a large remodeled adventitia”