Dynamic relation between myocardial contractility and energy metabolism during and following brief coronary occlusion in the pig.
Dynamic relation between myocardial contractility and energy metabolism during and following brief coronary occlusion in the pig.
复制标题
猪短暂冠状动脉闭塞期间和之后心肌收缩力和能量代谢之间的动态关系。
DOI：
10.1161/01.res.67.2.490
复制
发表时间：
1990
影响因子：
20.1
通讯作者：
Weiner,MW
中科院分区：
文献类型：
--
作者：
Schwartz,GG;Schaefer,S;Meyerhoff,DJ;Gober,J;Fochler,P;Massie,B;Weiner,MW
高能磷酸盐代谢的变化可能在缺血时心肌收缩功能的调节中起重要作用。本研究旨在确定短暂（24秒）冠状动脉闭塞期间和之后心肌收缩功能和高能磷酸盐代谢之间的动态关系，当这两个参数发生大而快速的变化时。8只麻醉开胸猪在冠状动脉前降支上安装多普勒血流探头和封堵器，在左心室前壁安装节段长度晶体，并安装表面线圈进行磷-31核磁共振波谱分析。磷-31光谱重建与4.8秒的时间分辨率通过求和相应的短块的数据从多个闭塞。在闭塞的前4.8秒期间，代谢和功能参数不变。在闭塞的剩余时间内，磷酸肌酸逐渐下降至对照组的66 +/- 3%，无机磷酸盐上升至对照组的170 +/- 8%，节段缩短下降至对照组的25 +/- 9%。一个强的线性相关性被发现之间的动态变化段缩短和磷酸肌酸（r2 = 0.97），无机磷酸盐（r2 = 0.96），磷酸肌酸无机磷酸盐（r2 = 0.98）在闭塞。在任何水平的磷酸肌酸和无机磷酸盐之间的比例，段缩短在回流期间比在闭塞。心肌节段缩短和磷代谢之间的密切动态关系支持缺血期间能量代谢或其副产物的变化对收缩性的调节。在反应性充血期间，高冠状动脉流速可能是调节收缩力的独立因素。
Changes in high-energy phosphate metabolism may be important in the regulation of myocardial contractile function during ischemia. This study sought to determine the dynamic relation between myocardial contractile function and high-energy phosphate metabolism during and following brief (24-second) coronary occlusion, when large and rapid changes in both parameters occur. Eight anesthetized, open-chest pigs were instrumented with a Doppler flow probe and occluder on the anterior descending coronary artery, segment length crystals in the anterior left ventricular wall, and a surface coil for phosphorus-31 nuclear magnetic resonance spectroscopy. Phosphorus-31 spectra were reconstructed with a 4.8-second time resolution by summing corresponding short blocks of data from multiple occlusions. Metabolic and functional parameters were unchanged during the first 4.8 seconds of occlusion. During the remainder of occlusion, phosphocreatine progressively declined to 66 +/- 3% of control, inorganic phosphate rose to 170 +/- 8% of control, and segment shortening fell to 25 +/- 9% of control. A strong linear correlation was found between dynamic changes in segment shortening and phosphocreatine (r2 = 0.97), inorganic phosphate (r2 = 0.96), and the ratio of phosphocreatine to inorganic phosphate (r2 = 0.98) during occlusion. At any level of the ratio between phosphocreatine and inorganic phosphate, segment shortening was greater during reflow than during occlusion. The close, dynamic relation between segment shortening and phosphorus metabolites supports the regulation of contractility by changes in energy metabolism or its by-products during ischemia. During reactive hyperemia, the high coronary flow rate may be an independent factor modulating contractility.