Kronauge J F, Leòn A S, Verdera E S, Balter H S, Leòn E T, Mut F, Oliveira M C, Garcia F A, Holman B L, Davison A
Department of Radiology, Harvard Medical School, Boston, Massachusetts.
J Nucl Med. 1992 Nov;33(11):1949-57.
The myocardial perfusion agent technetium (2-carbomethoxy-2-isocyano-propane)6+ (99mTc-CPI) is unique from other cationic technetium isonitrile complexes in that it exhibits moderate washout from the heart and rapid hepatobiliary clearance in animal models and human volunteers. Dynamic imaging and HPLC analysis were performed in humans and guinea pigs to outline the pharmacological basis of its pharmacokinetics. Enzymatic hydrolysis of the terminal ester groups in blood was found to occur at a moderate rate producing new species that have been shown not to accumulate in heart tissue. However, after extraction by the heart, liver or kidneys, the 99mTc-CPI complex undergoes metabolism at a much slower rate than observed in the blood. Differences in hydrolysis rate and products obtained indicate separate mechanisms of hydrolysis occurring in blood and other organs. It is proposed that the heart washout occurring after hydrolysis produces a neutral compound which is no longer retained by the negative cytosolic and mitochondrial membrane potentials in myocardial tissue.
心肌灌注剂锝（2-甲氧羰基-2-异氰基丙烷）6 +（99mTc-CPI）与其他阳离子锝异腈配合物不同，在动物模型和人类志愿者中，它从心脏的洗脱适中，且肝胆清除迅速。在人类和豚鼠身上进行了动态成像和高效液相色谱分析，以概述其药代动力学的药理学基础。发现血液中末端酯基的酶促水解以适中的速率发生，产生的新物质已被证明不会在心脏组织中蓄积。然而，在被心脏、肝脏或肾脏摄取后，99mTc-CPI配合物的代谢速率比在血液中观察到的要慢得多。水解速率和所得产物的差异表明在血液和其他器官中发生的水解机制不同。有人提出，水解后发生的心脏洗脱产生一种中性化合物，该化合物不再被心肌组织中的负性胞质和线粒体膜电位所保留。
