Supplementary Material for: Early Morphofunctional Changes in AngII-Infused Mice Contribute to Regional Onset of Aortic Aneurysm and Dissection

Aortic aneurysms and dissections are silent and lethal conditions, whose pathogenesis remains incompletely understood. Although angiotensin II (AngII)-infused ApoE−/− mice have been widely used to study aortic aneurysm and dissection, early morphofunctional alterations preceding the onset of these conditions remain unknown. The goal of this study was to unveil early morphofunctional changes underlying the onset of aneurysm and dissection. At 3 days post-AngII infusion, suprarenal abdominal aorta presented significant volumetric dilatation and microstructural damage. Ex vivo assessment of vascular reactivity of the suprarenal dissection-prone aorta and its side branches, showed an endothelial and contractile dysfunctions that were severe in the suprarenal aorta, moderate distally, and absent in the side branches, mirroring the susceptibility to dissection of these different vascular segments. Early and specific morphofunctional changes of the suprarenal aorta may contribute to the regional onset of aortic aneurysm and dissection by exacerbating the biomechanical burden arising from its side branches.

主动脉瘤与主动脉夹层（Aortic aneurysms and dissections）是隐匿且致命的疾病，其发病机制尚未完全阐明。尽管经血管紧张素II（AngII）灌注的载脂蛋白E基因敲除（ApoE−/−）小鼠已被广泛用于主动脉瘤与夹层的相关研究，但此类疾病发作前的早期形态功能改变仍未明确。本研究旨在揭示动脉瘤与夹层发作背后的早期形态功能变化。在血管紧张素II灌注后第3天，肾上腹主动脉出现显著的容积扩张与微观结构损伤。对易发生夹层的肾上主动脉及其侧支血管进行离体血管反应性评估，结果显示内皮功能与收缩功能障碍在肾上主动脉中最为严重，远端血管呈中度异常，而侧支血管未出现此类异常，这与不同血管节段对夹层的易感性相吻合。肾上主动脉的早期特异性形态功能改变，可能通过加剧其侧支血管带来的生物力学负荷，参与主动脉瘤与夹层的区域性发作。