Ca and InsP3 Receptor Signaling in Cardiac Myocytes

心肌细胞中的 Ca 和 InsP3 受体信号传导

• 批准号: 8207381
• 负责人: LOTHAR A BLATTER
• 金额: $ 42.59万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-01-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8207381
• 关键词: Adult; Affect; Arrhythmia; Atrial Fibrillation; Buffers; Calcium; Cardiac; Cardiac Myocytes; Cardiovascular Diseases; Cell Death; Cell Nucleus; Cells; Complex; Coupling; Development; Disease; Failure; Gene Transfer; Generations; Genetic Transcription; Goals; Health; Hearing; Heart; Heart Atrium; Heart Diseases; Heart Hypertrophy; Heart failure; Homeostasis; Hydrogenase; Hypertrophy; Image; Inositol; Instruction; Laser Scanning Confocal Microscopy; Lead; Measures; Mediating; Metabolic; Metabolism; Mitochondria; Morbidity - disease rate; Muscle Cells; Nitric Oxide; Nitric Oxide Synthase; Noise; Nuclear; Nuclear Export; Oryctolagus cuniculus; Oxidation-Reduction; Permeability; Play; Process; Production; Protein Isoforms; Receptor Signaling; Regulation; Research; Resolution; Rest; Role; Ryanodine Receptor Calcium Release Channel; Sarcoplasmic Reticulum; Second Messenger Systems; Signal Pathway; Signal Transduction; Source; Techniques; Testing; Tissues; Transgenic Mice; Ventricular; Wild Type Mouse; calmodulin-dependent protein kinase II; controlled release; cost; heart function; induced pluripotent stem cell; mitochondrial permeability transition pore; mortality; mouse model; photolysis; receptor; receptor function; research study; response; second messenger; transcription factor; transcription factor NF-AT c3; tripolyphosphate; uptake; voltage

PROJECT SUMMARY (See instructions): IPaR-dependent Ca release plays an important role for a wide variety of cardiac functions, including modulation of excitation-contraction coupling (ECC), generation of arrhythmia, modulation of mitochondrial function and regulation of Ca-dependent transcription factors in hypertrophy and hear failure. The overall goal of the proposed study is to 1) identify the mechanisms of IPsR-dependent Ca signaling for diastolic and systolic function, 2) determine the relationship between IPaR-dependent Ca release, mitochondrial Ca uptake and its effect on mitochondrial function, and 3) define the Ca-dependent mechanisms of isoform- and tissuespecific regulation of the hypertrophy transcription factor NFAT. The specific aims are: 1) test the hypothesis that IP3 receptor (IP3R)-dependent Ca release modulates diastolic (SR Ca leak) and systolic (positive inotropic and proarrhythmic effects) Ca signaling in normal adult myocytes and in cardiac hypertrophy and heart failure; 2) test the hypothesis that IPsR-dependent Ca release enhances mitochondrial Ca uptake and mitochondrial Ca-dependent functions (Ca-dependent hydrogenases and metabolic function; opening of the permeability transition pore; nitric oxide (NO) and ROS production by mitochondrial NOS, leading to altered cellular redox state); 3) identify Ca signaling pathways relevant for the activation of the transcription factor NFAT that initiates hypertrophic remodeling processes, and test the hypothesis that Ca-dependent regulation of NFAT is isoform- (NFATcl vs. NFATc3), tissue- (atrial vs. ventricle) and disease state- (normal vs. heart failure) specific and modulated by the redox state of the cell. To achieve these aims a multitude of experimental techniques will be used: high resolution imaging by laser scanning confocal microscopy in single myocytes to measure whole cell and subcellular [Ca]i, [Cajmito and [Ca]sR, whole-cell voltage and current clamp techniques, subcellular photolysis of caged Ca, adenoviral gene-transfer, and pharmacological manipulation of Ca transport and buffering. Experiments will be conducted on adult myocytes from wild-type mouse and rabbit, heart failure rabbit, and transgenic mouse models. The proposed research will provide fundamental new information on the cellular mechanism of Ca signaling relevant to the understanding of cardiac hypertrophy and failure.

项目摘要（参见说明）： IPaR 依赖性 Ca 释放在多种心脏功能中发挥着重要作用，包括兴奋收缩耦合 (ECC) 的调节、心律失常的产生、线粒体功能的调节以及肥厚和听力衰竭中 Ca 依赖性转录因子的调节。本研究的总体目标是 1) 确定 IPsR 依赖性 Ca 信号传导对舒张和收缩功能的影响机制，2) 确定 IPaR 依赖性 Ca 释放、线粒体 Ca 摄取及其对线粒体功能影响之间的关系，以及 3 ）定义同种型和组织特异性的 Ca 依赖性机制 肥大转录因子 NFAT 的调节。 具体目标是： 1) 检验 IP3 受体 (IP3R) 依赖性 Ca 释放调节正常成人肌细胞以及心脏肥大和心力衰竭中舒张（SR Ca 渗漏）和收缩（正性肌力和致心律失常作用）Ca 信号传导的假设； 2）检验IPsR依赖性Ca释放增强线粒体Ca摄取和线粒体Ca依赖性功能（Ca依赖性氢化酶和代谢功能；通透性转换孔的开放；线粒体NOS产生一氧化氮（NO）和ROS，导致改变细胞氧化还原 状态）; 3) 确定与启动肥大重塑过程的转录因子 NFAT 激活相关的 Ca 信号通路，并测试 NFAT 的 Ca 依赖性调节是异构体-（NFATcl 与 NFATc3）、组织-（心房与心室）的假设和疾病状态（正常与心力衰竭）特定并由细胞的氧化还原状态调节。 为了实现这些目标，将使用多种实验技术：通过激光扫描共聚焦显微镜在单个肌细胞中进行高分辨率成像，以测量全细胞和亚细胞 [Ca]i、[Cajmito 和 [Ca]sR、全细胞电压和电流钳技术、笼中 Ca 的亚细胞光解、腺病毒基因转移以及 Ca 转运和缓冲的药理学操作。实验将在野生型小鼠和兔子、心力衰竭兔子和转基因小鼠模型的成年肌细胞上进行。 拟议的研究将为了解心脏肥大和衰竭相关的 Ca 信号传导细胞机制提供基本的新信息。