Compared with the C57BL/6N substrain, the C57BL/6J substrain is more susceptible to the angiotensin II (Ang II)-induced development of dissected abdominal aortic aneurysms (AAAs). The aim of this study was to elucidate whether the widely used C57BL/6N mouse substrain is as susceptible as the C57BL/6J mouse substrain to porcine pancreatic elastase (PPE) infusion-induced experimental nondissected AAA development.
Experimental nondissected AAAs were induced in C57BL/6J and C57BL/6N mice via transient aortic luminal infusion of PPE. On Day 0 (baseline) and Day 14 after PPE infusion, the abdominal aortic diameter was directly measured. Aortic aneurysmal segment samples were collected, and histopathological analysis was performed.
On Day 14 after PPE infusion, aortic diameters were significantly increased in both mouse substrains (from approximately 0.51 to 1.24 mm in C57BL/6J mice and from 0.51 to 1.18 mm in C57BL/6N mice). The increase in diameter of all the mice exceeded 50% and met the criteria for AAA model establishment (143% and 135% in C57BL/6J mice and C57BL/6N mice, respectively). PPE infusion also induced obvious local aortic wall macrophage and
The C57BL/6N mouse substrain is suitable for establishing a model of AAA via elastase infusion.