Coronary ion channels, gender and vasoreactivity

冠状动脉离子通道、性别和血管反应性

• 批准号: 6910679
• 负责人: DOUGLAS K BOWLES
• 金额: $ 36.75万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6910679
• 关键词: blood vessel disorder; calcium channel; calcium flux; coronary artery; disease /disorder proneness /risk; electrophysiology; estrogens; fluorescence microscopy; gender difference; intermolecular interaction; polymerase chain reaction; potassium channel; protein kinase C; swine; testosterone; vascular smooth muscle; voltage /patch clamp; voltage gated channel; western blottings

DESCRIPTION (provided by applicant): Recent prospective clinical trials have underscored our lack of knowledge with regard to the effect of gender and sex hormones on the coronary vasculature, especially at the cellular/molecular level. Sex hormones exert profound influence on vascular smooth muscle physiology, including proliferation, ion channel activity and channel expression. Coronary smooth muscle (CSM) ion channel activity is central to both regulation of coronary blood flow and progression of vascular disease. We have demonstrated that CSM calcium and potassium channel activities are strongly influenced by gender. This study will determine the mechanism for gender-specific differences in CSM voltage-gated calcium (VGCC) and K channel activity and the consequent effects on intracellular calcium (Cai) regulation and vasoreactivity. The overall hypothesis is that coronary arterial reactivity in males is greater due to a testosterone (TST)-dependent increase in VGCC synthesis and PKC-dependent activity resulting in an enhanced propensity for coronary vasospasm (CVS). Both in vivo (intact, gonadectomized and hormone-replaced swine) and in vitro techniques will be used to determine the role of gender, TST and estrogen (E2) in regulating CSM ion channel activity and coronary arterial reactivity. Aim 1 will determine the mechanism of gender and sex hormone induced changes in VGCC activity and expression using electrophysiology, immunoblot and RT-PCR. As both vasoreactivity and VGCC activity are modulated by PKC, gender and sex hormone effects on PKC regulation of VGCC will also be examined. As the effect of VGCC activity on Cai and contraction is modulated via coupling to K channels and cellular calcium buffering, Aim 2 will determine the effect of sex-specific differences in VGCC activity on Ca-activated (BK) and voltage-dependent K current (Kv) and Cai using simultaneous voltage clamp and microfluorometry. The effect of sex-specific differences in VGCC activity on macro- and microvascular reactivity under both physiological and pathophysiological conditions will be assessed in vitro and in vivo in Aim 3. A model of CVS will be used to assess the role of sex-specific differences in VGCC activity on the progression and severity of vascular disease. The goal of this research is to determine gender-related cellular and molecular differences in CSM as they relate to gender differences in propensity for coronary disease.

描述（由申请人提供）：最近的前瞻性临床试验强调我们缺乏关于性别和性激素对冠状脉管系统的影响的知识，特别是在细胞/分子水平上。性激素对血管平滑肌生理学产生深远影响，包括增殖、离子通道活性和通道表达。冠状动脉平滑肌（CSM）离子通道活性对于冠状动脉血流的调节和血管疾病的进展至关重要。我们已经证明 CSM 钙和钾通道活性受性别的强烈影响。本研究将确定 CSM 电压门控钙 (VGCC) 和 K 通道活性的性别特异性差异的机制，以及对细胞内钙 (Cai) 调节和血管反应性的后续影响。总体假设是，由于 VGCC 合成中睾酮 (TST) 依赖性增加和 PKC 依赖性活性增加，导致冠状血管痉挛 (CVS) 倾向增强，男性冠状动脉反应性更强。体内（完整的、去性腺切除的和激素替代的猪）和体外技术将用于确定性别、TST和雌激素（E2）在调节CSM离子通道活性和冠状动脉反应性中的作用。目标 1 将利用电生理学、免疫印迹和 RT-PCR 确定性别和性激素诱导 VGCC 活性和表达变化的机制。由于血管反应性和 VGCC 活性均受 PKC 调节，因此还将检查性别和性激素对 VGCC PKC 调节的影响。由于 VGCC 活性对 Cai 和收缩的影响是通过与 K 通道和细胞钙缓冲耦合来调节的，因此目标 2 将确定 VGCC 活性的性别特异性差异对 Ca 激活 (BK) 和电压依赖性 K 电流的影响（ Kv) 和 Cai 使用同步电压钳和显微荧光测定法。在目标 3 中，将在体外和体内评估生理和病理生理条件下 VGCC 活性的性别特异性差异对大血管和微血管反应性的影响。CVS 模型将用于评估性别特异性差异的作用VGCC 活性对血管疾病的进展和严重程度的影响。本研究的目的是确定 CSM 中与性别相关的细胞和分子差异，因为它们与冠心病倾向的性别差异有关。