Persistent Calcium Sparklets in Arterial Smooth Muscle

动脉平滑肌中持续存在钙火花

• 批准号: 8806589
• 负责人: Luis F Santana
• 金额: $ 15.41万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-04-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8806589
• 关键词: Adrenergic Agents; Adult; Age; Agonist; Angiotensin II; Blood Pressure; Blood Vessels; Calcineurin; Calcium; Cell Nucleus; Cells; Cellular Membrane; Centers for Disease Control and Prevention (U.S.); Clinical; Complex; Coupled; Coupling; Data; Development; Dihydropyridines; Disease; Electrophysiology (science); Equilibrium; Event; Frequencies; Functional disorder; Funding; Gene Expression; Genetic Transcription; Health; Hypertension; Knock-in Mouse; Knockout Mice; Lead; Light; Location; Macromolecular Complexes; Methods; Modality; Modeling; Muscle Cells; Optics; PKC Binding Site; Phosphotransferases; Physiological; Physiological Processes; Play; Probability; Protein Kinase C Alpha; Proteins; Public Health; Regulation; Role; Sarcolemma; Signal Transduction; Smooth Muscle; Syndrome; System; Testing; Total Internal Reflection Fluorescent; Transgenic Organisms; Vascular Smooth Muscle; Work; adrenergic; calcineurin phosphatase; design; dihydropyridine; disorder prevention; hypertension treatment; innovation; mutant; novel; optogenetics; patch clamp; research study; transcription factor; transcription factor NF-AT c3; treatment strategy; voltage

DESCRIPTION (provided by applicant): The experiments in this application will test the hypothesis that clusters of voltage-gated L-type CaV1.2 channels are capable of undergoing coordinated openings ("coupled gating"), amplifying Ca2+ influx into arterial smooth muscle. A key discovery is that Ca2+ influx via coupled CaV1.2 channels plays a critical role in excitation-contraction (EC) coupling and excitation-transcription (ET) coupling in arterial myocytes. Preliminary data suggest that association of CaV1.2 channels with the anchoring protein AKAP150 is necessary for coupled gating activity in these cells. The significance of these findings is underscored by the observation that the frequency of coupled CaV1.2 gating events increases in arterial smooth muscle during hypertension and that loss of AKAP150 protects against coupled gating and hypertension. The project has two specific aims designed to investigate the mechanisms and physiological implications of these findings. Specific aim 1 is to test the hypothesis that coupled gating of CaV1.2 channels amplifies Ca2+ influx in arterial myocytes. Specific aim 2 is to test the hypothesis that AKAP150 is required for increased coupled CaV1.2 channel activity and the induction of arterial dysfunction during the development of hypertension. The methods that will be used to achieve these aims include patch-clamp electrophysiology, optical clamping, light- and chemically-induced dynamic targeting of kinases to cellular membranes, light-induced activation of adrenergic signaling (i.e., optogenetics), confocal, and TIRF microscopy. Experiments will involve new transgenic, knock in, and knock out mice. This work will generate fundamental information on the mechanisms by which AKAP150 and CaV1.2 channels control of excitability, gene expression, and EC coupling in vascular smooth muscle under physiological and pathological conditions.

描述（由申请人提供）：本申请中的实验将检验以下假设：电压门控L型CAV1.2通道能够进行协调的开口（“耦合门控”），从而扩大Ca2+涌入动脉平滑肌。一个关键的发现是，通过耦合CAV1.2通道的Ca2+涌入在动脉肌细胞中的激发 - 收缩（EC）耦合和激发转录（ET）耦合中起着至关重要的作用。初步数据表明，CAV1.2通道与锚定蛋白AKAP150的关联对于这些细胞中的耦合门控活性是必需的。这些发现的重要性强调了以下观察结果：耦合CAV1.2门控事件在高血压期间增加动脉平滑肌的频率增加，而AKAP150的丧失可以防止耦合的门控和高血压。该项目具有两个特定的目的，旨在研究这些发现的机制和生理含义。具体目的1是检验以下假设：CAV1.2通道的耦合耦合会扩增动脉心肌细胞的Ca2+流入。具体目的2是检验以下假设：AKAP150在高血压发展过程中增加偶联CAV1.2通道活性和动脉功能障碍所必需的偶联。将用于实现这些目标的方法包括斑板钳电生理学，光学夹紧，光和化学诱导的激酶对细胞膜的动态靶向，光诱导的肾上腺素信号的激活（即 光遗传学），共聚焦和TIRF显微镜。实验将涉及新的转基因，敲门和敲除小鼠。这项工作将生成有关AKAP150和CAV1.2在生理和病理条件下血管平滑肌中对兴奋性，基因表达和EC偶联的控制机制的基本信息。