Murine Arterial Aneurysm Model with CaCl2 and CSE

Ten-week-old male C57BL/6 mice were obtained from the Jackson Laboratory (Bar Harbor, ME, USA). The procedures for creating our modified CaCl₂-induced mouse model of arterial aneurysm were previously described [22 (link)]. Briefly, 0.5 M CaCl₂-soaked gauze was applied perivascularly for 20 min on the carotid artery as indicated. The gauze was replaced with another PBS-soaked or CSE-contained PBS-soaked gauze for 10 min, and the incised area was sutured. The mice were divided into two groups; CaCl₂ and PBS-soaked model (n = 10), and CaCl₂ and CSE-contained PBS-soaked model (n = 10). The mice were sacrificed 7 days after surgery, and the arteries were measured with an electronic digital caliper (VWR International, West Chester, PA, USA) and collected for histological examinations after fixing by perfusion with 4% PFA. For the flow cytometric analysis, the mice were also divided into two groups; CaCl₂ and PBS-soaked model (n = 5), and CaCl₂ and CSE-contained PBS-soaked model (n = 5). To obtain live cells for flow cytometry, the arteries were not fixed, but perfused with DMEM. All animal procedures were conducted in accordance with experimental protocols that were approved by the Institutional Animal Care and Use Committee at the University of Wisconsin, Madison (Protocol M005383).