权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Visualization of coronary microcirculation and neovascularization by synchrotron radiation microangiography

同步辐射微血管造影观察冠状动脉微循环和新生血管

基本信息

批准号：
15390371
负责人：
SAKAKIBARA Yuzuru
金额：
$ 9.54万
依托单位：
University of Tsukuba
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2005
项目状态：
已结题

项目摘要

1.Coronary Vasospasm4-aminopyridine (potassium channel blocker) induced coronary vasospasm effectively. Potassium channel is one of factors of coronary vasospasm. Spasm was induced in ovariectomized female rat rather than normal female rat. Female postponed recovery from spasm compared with male. Either acute or chronic withdrawal of estrogen is the risk factor of spasm. Blocker of eNOS (L-NNA) showed diffuse type of coronary spasm compared with 4-AP significantly. The angiographic shape of coronary spasm may indicate the mechanism of coronary spasm.2.Coronary neovascularizationAfter ligation of left anterior descending artery, rats were divided into two groups : control and infection of G-CSF (100μg/kg/day, 4 days). Rats with G-CSF injection showed increased collateral formation towards center of ischemia significantly.3.Neovascularization of acute ischemia in limbsLeft femoral artery of rat was ligated. Angiography was performed in pre-ligation and 1,7,14,28,56 days after ligation. Numbers of collateral arteries increased up to 28 days after ligation, whereas capillary formation was completed with 7 days after ligation. Completion of neovascularization was different depends on size and character of small vessels.4.Microvascular response of acute cold exposure in limbsRat hindlimb was exposed acute cold exposure by cold spray. While tissue temperature was decreased until 60 seconds after exposure, vessels enlarged immediately after cold exposure. Maximum distension reached to 225% at 60 seconds after exposure. This finding is different from commonly accepted theory.5.Microvascular response of acute cigarette smoking in limbArteries ranging from 100 to 500μm constricted by acute cigarette smoking, arteries less than 100mμm showed no changes. The constricted arteries recovered to previous size after cessation of smoking. Disturbance of acute cigarette smoking was limited to the arteries larger than 100μm. This meant vessel-size dependency the side effect of smoking.

1. 4-氨基吡啶（钾通道阻滞剂）能有效地诱发冠状动脉痉挛。钾通道是冠状动脉痉挛的因素之一。在去卵巢雌性大鼠而不是正常雌性大鼠中诱发痉挛。与男性相比，女性延迟从痉挛中恢复。急性或慢性雌激素戒断是痉挛的危险因素。eNOS阻断剂（L-NNA）与4-AP相比，表现为弥漫型冠脉痉挛。冠状动脉痉挛的血管造影形态可能反映冠状动脉痉挛的发生机制。2.冠状动脉新生血管结扎大鼠左前降支后，随机分为对照组和G-CSF感染组（100μg/kg/d，4d）。注射G-CSF后，缺血侧支血管形成明显增加。3.肢体急性缺血的新生血管形成结扎大鼠左股动脉。分别于结扎前、结扎后1、7、14、28、56天行血管造影。结扎后28天，侧支动脉数量增加，而毛细血管形成在结扎后7天完成。不同血管的大小和性质不同，新生血管的完成程度也不同。4.肢体急性冷暴露的微血管反应大鼠后肢经冷喷雾急性冷暴露。当组织温度降低到暴露后60秒时，血管在冷暴露后立即扩大。暴露后60秒最大扩张达到225%。5.急性吸烟对肢体微血管的影响急性吸烟使100 ~ 500μm的动脉收缩，小于100 μm的动脉无变化。戒烟后，收缩的动脉恢复到以前的大小。急性吸烟对动脉的损害仅限于直径大于100μm的动脉。这意味着血管大小依赖性吸烟的副作用。