Gap Junctions in Cell-Cell Communication (Supplement)

细胞间通讯中的间隙连接（补充）

• 批准号: 6645274
• 负责人: BRIAN R DULING
• 金额: $ 9.94万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-01-01 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6645274
• 关键词: arterioles; calcium flux; calcium indicator; cardiovascular function; cell cell interaction; electrophysiology; gap junctions; hamsters; laboratory mouse; membrane channels; membrane potentials; molecular genetics; muscle function; vascular endothelium; vascular smooth muscle; vasomotion

DESCRIPTION (provided by applicant): This is a proposal for a Competing Supplement to NHLBI grant #HL53318, Intercellular Communication in Microvessels. The overarching hypotheses or themes are that smooth muscle and endothelium function as an integrated unit in the regulation of cardiovascular function, and 2.) that the coordinating molecule uniting the two cell types is the connexin. The parent R-01 proposes to study three of the connexins; 43, 40, and 37. Knockout animals for connexin 40 and 37 have been obtained from a collaborator. Because deletion of the connexin 43 is embryologically lethal, we have created cell-specific knockouts in which connexin 43 expression is selectively eliminated in either smooth muscle or endothelium. At the time of submission of the parent R-01 grant we indicated that fuller understanding of the biology of the connexins in the vessel wall would necessitate the production of double knockouts through appropriate cross breeding. We selected connexin 43 and 40 as the first double knockout to be produced based on the facts that we could restrict deletion of 43 to the endothelium, and that our immuno-cytochemistry shows connexin 40 in the mouse to be abundantly expresses in the endothelium compared to the other connexins. We have now found that the endothelial cell-specific Cx43 KO crossed with the Cx40 KO produces rapidly advancing hypertension, profound cardiac hypertrophy and failure at about 3 months of age. The phenotype appears to be a model for overload cardiac hypertrophy and failure. Importantly, animal heterozygous for the endothelial cell deletion show a similar phenotype attesting to the penetrance of the phenotype. We have established a collaboration with the cardiac MRI group here and are now able to measure the progression of cardiac adaptation and failure in this model. These data support the need for an accelerated breeding program to designed to generate sufficient double knockouts, and to apply high throughput screening to the assessment of function. The specific aims of the Competing Supplement are: 1. to expand our breeding and animal maintenance to allow us to explore the vascular function in animals with double connexin knockouts. 2. to conduct longitudinal measurements on changes in cardiovascular physiology caused by the elimination of one or more of the connexin genes. Specifically, we will follow blood pressure, cardiac output, heart rate, EKG, and peripheral resistance, over several months of the development of hypertension, cardiac hypertrophy and ultimately failure. These data will be correlated with our ongoing measurements of microvascular function.

描述（由申请人提供）：这是对NHLBI赠款＃HL53318的竞争补充的提案，Microvesels中的细胞间通信。总体假设或主题是平滑的肌肉和内皮在心血管功能调节中的综合单元，以及2.）。父级R-01建议研究三种连接素。 43、40和37。连接40和37的淘汰动物是从合作者那里获得的。由于连接蛋白43的缺失在胚胎学上是致命的，因此我们创建了细胞特异性敲除，其中连接蛋白43表达在平滑肌或内皮中有选择地消除。 在服从父级R-01赠款时，我们指出，对容器壁中连接蛋白的生物学的更深入了解将有必要通过适当的跨育种产生双重敲除。我们选择了连接蛋白43和40作为基于我们可以将43删除的事实限制在内皮中产生的第一个双重敲除，并且与其他粘蛋白相比，我们的免疫环化学显示了小鼠中的连接蛋白40在内皮中表现出丰富的表达。现在，我们发现内皮细胞特异性的CX43 KO与CX40 KO越过，可在大约3个月大时产生快速前进的高血压，深层心脏肥大和衰竭。表型似乎是过载心脏肥大和失败的模型。重要的是，内皮细胞缺失的动物杂合子显示出与表型的渗透性相似的表型。我们在这里与心脏MRI组建立了合作，现在能够测量此模型中心脏适应和失败的进展。这些数据支持加速育种计划的需求，旨在产生足够的双重敲除，并将高吞吐量筛选用于功能评估。竞争补充剂的具体目的是：1。扩展我们的繁殖和动物维护，以使我们能够探索具有双连接蛋白敲除动物的血管功能。 2。通过消除一个或多个连接蛋白基因引起的心血管生理变化进行纵向测量。具体而言，在高血压，心脏肥大和最终失败的几个月内，我们将遵循血压，心脏输出，心率，心率和外周电阻。这些数据将与我们正在进行的微血管功能的测量相关。