Amano J, Sunamori M, Okumura T, Kameda T, Suzuki A
Jpn Circ J. 1982 Dec;46(12):1345-52. doi: 10.1253/jcj.46.1345.
Aspartate aminotransferase (EC 2.6.1.1:AST) is known to have two isoenzymes, one associated with the cytoplasm (c-AST) and the other with the mitochondria (m-AST). We studied the relationships of m-AST activity in the coronary sinus blood to left ventricular function, coronary blood flow, water content and high-energy phosphate stores of the left ventricle following hypothermic ischemic cardiac arrest. Under cardiopulmonary bypass with hypothermia of 20 degrees C of myocardial temperature, 120 min of aortic occlusion was employed in 15 mongrel dogs. Left ventricular function (peak left ventricular pressure, left ventricular end-diastolic pressure, max dp/dt, cardiac index, left ventricular stroke work index), coronary blood flow, myocardial oxygen consumption, myocardial enzyme activity (m-AST, CK-MB), myocardial water content and high-energy phosphate stores (adenosine triphosphate, creatine phosphate) of the subendocardium of the left ventricle were measured. Data was obtained in the control state, and after 0, 30 and 60 min of reperfusion. Significant negative correlations were obtained between m-AST activity and peak left ventricular pressure (r = -0.81, p less than 0.001), max dp/dt (r = -0.83, p less than 0.001), cardiac product (r = -0.73, p less than 0.01), coronary blood flow (r = -0.59, p less than 0.05), adenosine triphosphate level (r = 0.72, p less than 0.01) and creatine phosphate level (r = -0.72, p less than 0.02) after 60 min of reperfusion. Significant positive correlations were obtained between m-AST activity and left ventricular end-diastolic pressure (r=0.75, p less than 0.01) and water content (r = 0.78, p less than 0.01) after 60 min of reperfusion. These results led to the assumption that serum m-AST activity in the coronary venous blood is a useful index to evaluate the degree of myocardial injury.
天冬氨酸转氨酶（EC 2.6.1.1：AST）已知有两种同工酶，一种与细胞质相关（c-AST），另一种与线粒体相关（m-AST）。我们研究了低温缺血性心脏骤停后冠状窦血中m-AST活性与左心室功能、冠状动脉血流量、左心室含水量和高能磷酸储存之间的关系。在心肌温度为20℃的低温体外循环下，对15只杂种犬进行了120分钟的主动脉阻断。测量了左心室功能（左心室峰值压力、左心室舒张末期压力、最大dp/dt、心脏指数、左心室每搏功指数）、冠状动脉血流量、心肌耗氧量、心肌酶活性（m-AST、CK-MB）、左心室心内膜下的心肌含水量和高能磷酸储存（三磷酸腺苷、磷酸肌酸）。在对照状态下以及再灌注0、30和60分钟后获取数据。再灌注60分钟后，m-AST活性与左心室峰值压力（r = -0.81，p < 0.001）、最大dp/dt（r = -0.83，p < 0.001）、心输出量（r = -0.73，p < 0.01）、冠状动脉血流量（r = -0.59，p < 0.05）、三磷酸腺苷水平（r = 0.72，p < 0.01）和磷酸肌酸水平（r = -0.72，p < 0.02）之间存在显著负相关。再灌注60分钟后，m-AST活性与左心室舒张末期压力（r = 0.75，p < 0.01）和含水量（r = 0.78，p < 0.01）之间存在显著正相关。这些结果表明，冠状静脉血中的血清m-AST活性是评估心肌损伤程度的有用指标。
