Chloride channels in endothelial cells

项目摘要 内皮细胞调节多种血管功能，包括收缩性，其调节器官的功能。 血流量和全身血压。几乎所有心血管疾病的一个特点是功能障碍 内皮细胞，但涉及的病理机制是不确定的。几个阳离子通道表示 在调节动脉收缩力的EC中，包括小电导（SK）和中电导（IK）钙离子 (Ca2+）-激活钾通道和瞬时受体电位通道，包括TRPV 4。与此相反， EC中阴离子通道的生理功能知之甚少。EC表达TMEM 16 A，一种Ca 2 +- 激活的Cl-通道，但这种阴离子通道是否调节动脉收缩性尚不清楚。类似地 内皮细胞TMEM 16 A通道在血管功能障碍中的病理参与尚不确定 发生在高血压期间。使用广泛的方法，包括他莫昔芬诱导的内皮细胞 细胞特异性敲除小鼠，我们提供的证据表明，血管扩张刺激激活TMEM 16 A通道， 内皮细胞诱导血管舒张。初步数据还表明，内皮细胞TMEM 16 A通道 在高血压时功能失调。在本建议中，我们将探讨三个具体目标。目标1将 研究生理性血管扩张剂激活内皮细胞TMEM 16 A通道的信号传导机制 以诱导血管舒张。目的2将研究TMEM 16 A通道激活的机制， 内皮细胞促进血管舒张。目的3将研究高血压与 内皮细胞中TMEM 16 A通道的病理学改变，其抑制这些蛋白的血管舒张。 使用的方法将包括分子生物学和生物化学技术，超分辨率 免疫荧光显微镜、高速双倒置选择性平面照明显微镜（diSPIM） 双光子共聚焦显微镜，膜片钳和传统的电生理学，动脉肌电图和 无线电遥测该项目将提供有关生理和病理的重要新信息 通过内皮细胞中的TMEM 16 A通道进行血管调节。

Project Summary Endothelial cells regulate a wide variety of vascular functions, including contractility, which modulates organ blood flow and systemic blood pressure. A hallmark of virtually all cardiovascular diseases is dysfunctional endothelial cells, but pathological mechanisms involved are uncertain. Several cation channels are expressed in ECs that modulate arterial contractility, including small- (SK) and intermediate (IK)-conductance calcium (Ca2+)-activated potassium channels and transient receptor potential channels, including TRPV4. In contrast, physiological functions of anion channels in ECs are poorly understood. ECs express TMEM16A, a Ca2+- activated Cl- channel, but whether this anion channel regulates arterial contractility is unclear. Similarly uncertain is the pathological involvement of endothelial cell TMEM16A channels in the vascular dysfunction that occurs during hypertension. Using a broad range of approaches, including tamoxifen-inducible endothelial cell-specific knockout mice, we provide evidence that vasodilator stimuli activate TMEM16A channels in endothelial cells to induce vasodilation. Preliminary data also suggest that endothelial cell TMEM16A channels are dysfunctional during hypertension. In this proposal, we will investigate three specific aims. Aim 1 will investigate the signaling mechanisms by which physiological vasodilators activate TMEM16A channels in ECs to induce vasorelaxation. Aim 2 will examine the mechanisms by which the activation of TMEM16A channels in endothelial cells elicits vasodilation. Aim 3 will study the hypothesis that hypertension is associated with pathological alterations in TMEM16A channels in endothelial cells which inhibits vasodilation by these proteins. Methods used will include molecular biology and biochemistry techniques, super-resolution immunofluorescence microscopy, high-speed dual-inverted selective plane illumination microscopy (diSPIM), two-photon confocal microscopy, patch-clamp and conventional electrophysiology, arterial myography and radiotelemetry. This project will provide significant novel information regarding physiological and pathological vasoregulation by TMEM16A channels in endothelial cells.