SUBSTRATE-RELATED AND INHIBITOR-RELATED CHARACTERISTICS OF HUMAN PLATELET MONOAMINE-OXIDASE
SUBSTRATE-RELATED AND INHIBITOR-RELATED CHARACTERISTICS OF HUMAN PLATELET MONOAMINE-OXIDASE
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DOI：
10.1016/0006-2952(77)90398-7
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发表时间：
1977-01-01
影响因子：
5.8
通讯作者：
MURPHY, DL
中科院分区：
文献类型：
--
作者：
DONNELLY, CH;MURPHY, DL
与A型MAO的底物5-羟色胺相比，人血小板单胺氧化酶(MAO)[EC 1.4.3.4]优先脱氨化B型MAO的两种底物--苯甲胺和苯乙胺。在比较人血小板和大鼠脑MAO比活性的研究中，血小板对苯甲胺和5-羟色胺的脱氨率分别约为脑的90%和2%，而对多巴胺、色胺和酪胺的脱氨率约为脑的20%或更少。在所研究的16种药物中，低浓度MAO-B抑制剂丙戊烯和帕吉林选择性地抑制血小板MAO活性，而对MAO-A抑制剂Clorgyline和Lilly 51641[N-[2-(邻氯苯氧乙基)乙基]环丙胺盐酸盐]相对不敏感。这些观察结果，除了随着氯吉林或丙戊烯基浓度的增加而获得的简单的S形抑制曲线外，还表明血小板MAO基本上由一种可区分的MAO组成，它最接近于在其他组织中发现的MAO的B型。
Human platelet monoamine oxidase (MAO) [EC 1.4.3.4] preferentially deaminated benzylamine and phenylethylamine, 2 substrates relatively specific for type B MAO, in comparison to 5-hydroxytryptamine, a substrate specific for type A MAO. In studies comparing human platelet and rat brain MAO specific activities, benzylamine and 5-hydroxytryptamine deamination by platelets was approximately 90 and 2%, respectively, that of brain, while platelet deamination of dopamine, tryptamine and tyramine was 20% or less than that of brain. Among 16 drugs studied, platelet MAO activity was selectively inhibited by low concentrations of the MAO-B inhibitors, deprenyl and pargyline, and was relatively insensitive to the MAO-A inhibitors, clorgyline and Lilly 51641 [N-[2-(o-chlorophenoxy)ethyl]cyclopropylamine hydrochloride]. These observations, in addition to the simple sigmoid inhibition curves obtained with increasing concentrations of either clorgyline or deprenyl, suggest that platelet MAO consists of essentially 1 distinguishable form of MAO which most closely resembles the MAO type B found in other tissues.