VALIDATION OF [1-C-11]ACETATE AS A TRACER FOR NONINVASIVE ASSESSMENT OF OXIDATIVE-METABOLISM WITH POSITRON EMISSION TOMOGRAPHY IN NORMAL, ISCHEMIC, POSTISCHEMIC, AND HYPEREMIC CANINE MYOCARDIUM
VALIDATION OF [1-C-11]ACETATE AS A TRACER FOR NONINVASIVE ASSESSMENT OF OXIDATIVE-METABOLISM WITH POSITRON EMISSION TOMOGRAPHY IN NORMAL, ISCHEMIC, POSTISCHEMIC, AND HYPEREMIC CANINE MYOCARDIUM
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DOI：
10.1161/01.cir.81.5.1594
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发表时间：
1990-05-01
期刊：
影响因子：
37.8
通讯作者：
SCHELBERT, HR
中科院分区：
文献类型：
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作者：
ARMBRECHT, JJ;BUXTON, DB;SCHELBERT, HR
在 30 只开胸狗身上进行的 65 项实验中检查了 [1-11C]乙酸盐的提取和清除动力学。 29 项研究在对照组进行，13 项在缺血期间进行，8 项在再灌注后进行，13 项在双嘧达莫引起的充血期间进行，2 项在心脏负荷改变期间进行。 [1-11C]乙酸盐直接注入左冠状动脉前降支，用伽马探针记录心肌组织-时间活动曲线。单程萃取分数平均为 64.2±。 9.7% 为对照，65.3 .+-。 9.1% 缺血，70.0 .+-。再灌注为 4.4%，46.5 .+-。双嘧达莫引起的充血组为 7.4%。在所有情况下 11C 清除率都是双指数的。在对照组、缺血组、再灌注组和双嘧达莫诱导组中，第一个快速清除阶段的速率常数 k1 与心肌耗氧量密切相关 (r = 0.94)。仅对清除率曲线的第一个线性部分进行单指数拟合得出速率常数 kmono，它也与心肌耗氧量相关 (r = 0.96)。动脉乳酸浓度和心肌消耗的游离脂肪酸氧当量对[1-11C]乙酸清除率常数和心肌耗氧量之间的关系具有微小但具有统计学意义的影响。同时注射[1-14C]乙酸盐后离开心肌的 14CO2 活性分数 (n = 24) 相对较高（对照中为 97.4 .+-. 2.5%，缺血中为 89 .+-. 2.6%，再灌注中为 94.1 .+-. 3.5%，双嘧达莫中 > 99%）组），表明外部测量的 11C 清除率对应于 CO2 产生，从而对应于三羧酸循环活性。总之，结果验证了[1-11C]乙酸盐作为氧化心肌代谢示踪剂用于正电子发射断层扫描的用途。
Extraction and clearance kinetics of [1-11C]acetate were examined in 65 experiments in 30 open-chest dogs. Twenty-nine studies were performed at control, 13 during ischemia, eight after reperfusion, 13 during dipyridamole-induced hyperemia, and two during alteration of cardiac workload. [1-11C]Acetate was injected directly into the left anterior descending coronary artery, and myocardial tissue-time activity curves were recorded with a gamma probe. The single-pass extraction fraction averaged 64.2 .+-. 9.7% in control, 65.3 .+-. 9.1% in ischemia, 70.0 .+-. 4.4% in reperfusion, and 46.5 .+-. 7.4% in dipyridamole-induced hyperemia groups. 11C clearance was biexponential in all cases. The rate constant k1 for the first rapid clearance phase correlated closely with myocardial oxygen consumption (r = 0.94) in control, ischemia, reperfusion, and dipyridamole-induced groups. Monoexponential fitting of only the first linear part of the clearance curve yielded the rate constant kmono, which also correlated with myocardial oxygen consumption (r = 0.96). Arterial lactate concentrations and the amount of free fatty acid oxygen equivalents consumed by the myocardium were shown to have a small but statistically significant impact on the relation between [1-11C]acetate clearance rate constants and myocardial oxygen consumption. The fraction of 14CO2 activity contributing to overall 14C activity leaving the myocardium after simultaneous injection of [1-14C]acetate (n = 24) was relatively high in all cases (97.4 .+-. 2.5% in control, 89 .+-. 2.6% in ischemia, 94.1 .+-. 3.5% in reperfusion, and > 99% in dipyridamole groups), indicating that externally measured 11C clearance corresponds to CO2 production and thus to tricarboxylic acid cycle activity. In conclusion, the results validate the use of [1-11C]acetate as a tracer of oxidative myocardial metabolism for use with positron emission tomography.