Coronary arteriolar myogenic response in regulation of coronary circulation

冠状动脉生肌反应对冠状循环的调节

• 批准号: 03670471
• 负责人: TSUJIOKA Katsuhiko
• 金额: $ 1.34万
• 依托单位: Kawasaki Medical School
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03670471/
• 关键词: Coronary regulation; Coronary arteriole; Myogenic response; CCD microscope; Reactive hypermia; Nitroglycerine; Prolonged diastole; ビデオ生体顕微鏡

Coronary blood flow has a sophisticated control system including three major mechanisms : (1) "autoregulation" which keeps blood flow rate constant when perfusion pressure is changed, (2) "reactive hypermia" in reperfusion after short-time coronary artery occlusion, and (3) "an increase in bolld flow rate due to load" when myocardial oxygen consumption rate increases. This coronary blood flow control is considered "concerted control" of various mechanisms such as metabolic factors (adenosine, Pco2,and Po2) and control factors via endothelium. In this study, we focus "myocardial control" which has recently been a popular research topic. Our main goals are to study the effects of this control mechanism under the coronary blood flow controlling condition including "autoregulation," "reactive hypermia,) and "an increase in blood flow rate due to load," and then to clarity the significance of these effects during pathological conditions such as myocardial ischemia.In this report, we present … More the results for in vivo experiments in which we have made great advancement. A needle-probe CCD microscope was used to observe the microvessels in subendo- and subepi-cardial sides. The microvessels in the epi-cardial side was observed by gently contacting the probe to observation spots. Those in the subendo-cardial side was observed by introducing the probe through left arterial appendage into left ventricle and contacting it to observation spots. The blood around the probe was flushed with a Krebs-Ringer solution (37ﾟC). The diameter of the arteriole in the subepicardial side increased during systole while that in the subendocardial side decreased about 20 % during systole. as for the reaction of the arteriole at reactive hypermia by 20-sec blood flow hold, the diameter was maximum about 20 sec and returned to the initial value after about one min. The blood vessels in the subendocardial side needed longer time to return to the initial value than in those in the subepicardial side. When the prolonged diastole was induced by an AV block, the diameter of coronary arteriole decreased with decreasing aortic pressure. In contrast, that of coronary venule increased first and then reached a steady value. Nitroglycerine increased the diameter of both coronary arteriole and venule, and also increased the extent of the change in the diameter over a heart cycle. Less

冠状动脉血流具有复杂的控制系统，包括三个主要机制：（1）“自动调节”，当灌注压改变时保持血流速率恒定，（2）冠状动脉短暂闭塞后再灌注时的“反应性高血”，和（3）当心肌耗氧速率增加时“负荷引起的血流速率增加”。这种冠状动脉血流控制被认为是各种机制的“协调控制”，例如代谢因子（腺苷、Pco 2和Po 2）和经由内皮的控制因子。在本研究中，我们将重点放在“心肌控制”，这是最近一个热门的研究课题。我们的主要目标是研究这种控制机制在冠状动脉血流控制条件下的作用，包括“自动调节”、“反应性高血”和“负荷增加血流速度”，然后阐明这些作用在病理条件下的意义，如心肌缺血。 ...更多信息 体内实验的结果，我们已经取得了很大的进展。用针探针CCD显微镜观察内、上腹侧微血管。通过将探针轻轻接触观察点来观察上皮侧中的微血管。通过将探头经左动脉附件插入左心室，并与观察点接触，观察心内膜下侧。用Krebs-Ringer溶液（37 ℃）冲洗探针周围的血液。心外膜下侧的微动脉直径在收缩期增大，而心内膜下侧的微动脉直径在收缩期减小约20%。反应性高血时小动脉血流保持20秒时，其内径在20秒左右达到最大值，约1分钟后恢复到初始值，心内膜下侧血管恢复到初始值所需时间较心外膜下侧长。当房室传导阻滞引起冠状动脉延长时，冠状动脉直径随主动脉压降低而减小。冠状微静脉的血流速度则先增加后趋于稳定。硝酸甘油使冠状小动脉和小静脉的直径增加，并使直径在一个心动周期内的变化程度增加。少

项目成果

Fumihiko Kajiya, et al: "Blood Velocity Patterns in Poststenotic Regions and Velocity Waveforms for Myocardial Inflow Associated with Coronary Artery Stenosis in Dog" Transactions of SAME Journal of Biomechanical Engineering. 114. 385-390 (1992)

Fumihiko Kajiya 等人：“狭窄后区域的血流速度模式和与​​狗冠状动脉狭窄相关的心肌流入的速度波形”SAME 生物力学工程学杂志的交易。

AKihiro Kimura,et al.: "Direct Effect of Nitroglycerin on Phasic Pattern and Transmyocardial Distribition of Flow during Fixed Coronary Artery Stenosis" Nihon-Igakukan, 2 (1991)

AKihiro Kimura 等人：“硝酸甘油对固定冠状动脉狭窄期间血流的相位模式和跨心肌分布的直接影响”Nihon-Igakukan，2 (1991)

Fumihiko KAJIYA,et al: "A Study of Coronary Circulation by Laser Doppler Velocimetry" Springer-Verlag, 13 (1991)

Fumihiko KAJIYA 等人：“激光多普勒测速法对冠状动脉循环的研究”Springer-Verlag，13 (1991)

Akihiro Kimura, et al: "Direct Effect of Nitroglycerin on Phasic Pattern and Transmyocardial Distribution of Flow during Fixed Coronary Artery Stenosis" Microcirculation annual 1991 Nihon-Igakukan. 109-110 (1991)

Akihiro Kimura 等人：“硝酸甘油对固定冠状动脉狭窄期间血流的相位模式和跨心肌分布的直接影响”微循环年鉴 1991 年日本医学馆。

Fumihiko Kajiya(eds:M.Nakamura,P.M.Vangoutte): "Characteristics and Possible Prigins of Blood Velocity waveform of the Epicardial and Intramyocardial Coronary Circulation in the Ventricular and the Atria In Coronary Circulation in Physiological and Pathop

Fumihiko Kajiya（编辑：M.Nakamura，P.M.Vangoutte）：“生理学和病理学冠状动脉循环中心室和心房的心外膜和心肌内冠状动脉循环的血流速度波形的特征和可能的起源”