Wang ShengPeng, Iring András, Strilic Boris, Albarrán Juárez Julián, Kaur Harmandeep, Troidl Kerstin, Tonack Sarah, Burbiel Joachim C, Müller Christa E, Fleming Ingrid, Lundberg Jon O, Wettschureck Nina, Offermanns Stefan
J Clin Invest. 2015 Aug 3;125(8):3077-86. doi: 10.1172/JCI81067. Epub 2015 Jul 13.
Elevated blood pressure is a key risk factor for developing cardiovascular diseases. Blood pressure is largely determined by vasodilatory mediators, such as nitric oxide (NO), that are released from the endothelium in response to fluid shear stress exerted by the flowing blood. Previous work has identified several mechanotransduction signaling processes that are involved in fluid shear stress-induced endothelial effects, but how fluid shear stress initiates the response is poorly understood. Here, we evaluated human and bovine endothelial cells and found that the purinergic receptor P2Y2 and the G proteins Gq/G11 mediate fluid shear stress-induced endothelial responses, including [Ca2+]i transients, activation of the endothelial NO synthase (eNOS), phosphorylation of PECAM-1 and VEGFR-2, as well as activation of SRC and AKT. In response to fluid shear stress, endothelial cells released ATP, which activates the purinergic P2Y2 receptor. Mice with induced endothelium-specific P2Y2 or Gq/G11 deficiency lacked flow-induced vasodilation and developed hypertension that was accompanied by reduced eNOS activation. Together, our data identify P2Y2 and Gq/G11 as a critical endothelial mechanosignaling pathway that is upstream of previously described mechanotransduction processes and demonstrate that P2Y2 and Gq/G11 are required for basal endothelial NO formation, vascular tone, and blood pressure.
血压升高是心血管疾病发生的关键危险因素。血压很大程度上由血管舒张介质决定,如一氧化氮(NO),它是内皮细胞在血流施加的流体剪切应力作用下释放的。先前的研究已经确定了几种参与流体剪切应力诱导的内皮效应的机械转导信号传导过程,但流体剪切应力如何引发这种反应却知之甚少。在这里,我们评估了人和牛的内皮细胞,发现嘌呤能受体P2Y2和G蛋白Gq/G11介导流体剪切应力诱导的内皮反应,包括[Ca2+]i瞬变、内皮型一氧化氮合酶(eNOS)的激活、PECAM-1和VEGFR-2的磷酸化,以及SRC和AKT的激活。响应流体剪切应力时,内皮细胞释放ATP,它激活嘌呤能P2Y2受体。诱导内皮特异性P2Y2或Gq/G11缺陷的小鼠缺乏血流诱导的血管舒张,并出现高血压,同时伴有eNOS激活减少。总之,我们的数据确定P2Y2和Gq/G11是一种关键的内皮机械信号通路,它位于先前描述的机械转导过程的上游,并证明P2Y2和Gq/G11是基础内皮NO形成、血管张力和血压所必需的。