Supplementary Material for: No Protective Effect of Constitutive Activation of AMPK in Endothelial Cells on Vascular Function in Aged Obese Mice but Augmented α1-Adrenergic Contractions in Renal Arteries Reversible by Weight Loss

<b><i>Background:</i></b> Aging, obesity, and diabetes favor vascular dysfunction. Endothelial activation of adenosine monophosphate-activated protein kinase (AMPK) has protective effects in diabetes. <b><i>Methods:</i></b> Mice with constitutive endothelial activation of AMPK (CA-AMPK) were given a high fat diet to induce obesity or kept on standard chow as lean controls for up to 2 years. A subset of obese animals was changed to standard chow after 30 weeks of high fat feeding. En­dothelium-dependent and endothelium-independent responses were examined by isometric tension recording. <b><i>Results and Conclusion:</i></b> Endothelium-dependent nitric oxide (NO)- and apamin <i>plus</i> charybdotoxin-sensitive relaxations were preserved and similar between aortic or renal arterial preparations of lean and obese CA-AMPK mice and their wild-type littermates. Despite comparable release of vasoconstrictor prostanoids, cyclooxygenase-dependent contractions were enhanced during NO synthase inhibition in carotid arterial rings of obese CA-AMPK mice. Contractions to the α₁-adrenoceptor agonist phenylephrine were augmented in renal arteries of obese animals, a genotype-independent phenomenon reversible by weight loss. These data indicate a higher α₁-adrenergic reactivity in renal arteries of aged mice with obesity. The current results highlight the potential of weight loss to alleviate vascular dysfunction. However, endothelial activation of the AMPK pathway in obesity may not be sufficient to prevent vascular dysfunction without lifestyle changes.

**<i>背景：</i>** 衰老、肥胖与糖尿病均会促进血管功能障碍。腺苷一磷酸激活的蛋白激酶（adenosine monophosphate-activated protein kinase, AMPK）的内皮激活对糖尿病具有保护作用。**<i>方法：</i>** 本研究采用组成型内皮AMPK激活（CA-AMPK）小鼠，给予高脂饮食以诱导肥胖，或维持普通饲料喂养作为瘦型对照，造模周期长达2年。其中部分肥胖小鼠在高脂喂养30周后转换为普通饲料喂养。通过等长张力记录法检测内皮依赖性与内皮非依赖性血管反应。**<i>结果与结论：</i>** 瘦型与肥胖型CA-AMPK小鼠及其野生型同窝对照的主动脉或肾动脉标本中，内皮依赖性一氧化氮（nitric oxide, NO）敏感舒张以及阿帕明（apamin）联合查巴克毒素（charybdotoxin）敏感舒张均得以保留，且两组间无显著差异。尽管缩血管前列腺素的释放水平相当，但在一氧化氮合酶抑制状态下，肥胖型CA-AMPK小鼠的颈动脉环的环氧合酶依赖性收缩增强。肥胖小鼠肾动脉对α₁-肾上腺素能受体激动剂苯肾上腺素的收缩反应增强，这一现象不依赖于基因型，且可通过体重减轻逆转。本研究数据表明，老年肥胖小鼠肾动脉的α₁-肾上腺素能反应性更高。本研究结果凸显了体重减轻缓解血管功能障碍的潜力。然而，肥胖状态下AMPK通路的内皮激活若不伴随生活方式改变，可能不足以预防血管功能障碍。