Studies of plasma PEA and platelet MAO in affective disorders

-苯乙胺（PEA）是一种内源性单胺，其化学结构类似于安非他明，已在人类和其他哺乳动物的大脑中被发现。虽然PEA的存在量比儿茶酚胺少得多，但PEA作为神经调节剂的作用方式引起了人们的特别关注。最近，越来越多的临床证据表明PEA在情感性障碍中起作用。作者研究了一种气相色谱质谱法测定人血浆中PEA的灵敏方法。用这种新方法测定抑郁症患者血浆PEA水平。将抑郁患者分为PEA高、低两组。低血浆PEA患者给予去甲基咪帕明后生长激素反应低，血浆中3 -甲氧基4羟基苯乙二醇（MHPG）升高。另一组抑郁症患者去甲咪帕明试验生长激素反应正常，血浆MHPG水平低。同时测定患者血小板单胺氧化酶（MAO）活性。部分患者血小板MAO可加性增高。而抑郁患者的血小板MAO活性与健康人相比无明显升高。上述结果提示，抑郁症患者血浆PEA水平在两个亚组之间的差异，增加了组间临床差异的可能性，血浆PEA可能是抑郁症患者的生物学标志物之一。这些结果将在1990年CINP专题讨论会上报告。

beta-phenylethylamine(PEA), an endogenous monoamine that resembles amphetamine in its chemical structure, has been identified in human and other mammalian brains. Although PEA exists in much smaller amounts than catecholamines, the mode of action of PEA as a neuromodulator is of special interest. Recently, there has been growing clinical evidence suggesting that PEA plays a role in affective disorders. The authors investigated a sensitive method for the assay of PEA in human plasma, using a gas-chromatography mass spectrometry.The plasma levels of PEA was measured in depressive patients by this new method. The depressive patients were divided into those with high and low PEA levels. The low response of growth hormone after the desmethylimipramine administration and higher 3methoxy 4hydroxy phenylethyleneglycol(MHPG) in plasma were shown in the patients with low plasma levels of PEA. The normal response of growth hormone by desmethylimipramine test and low plasma levels of MHPG were found in the other group of depressive patients. Platelet monoamine oxidase(MAO) activity was also determined in those patients. The higher platelet MAO additivity was found in some patients. But, platelet MAO activity in the depressive patients was not significantly increased, compared with the healthy subjects.These results suggest that the distinction of PEA levels between two subgroups in depressive patients raise the possibility of clinical differences between the groups, and that PEA in plasma might be one of biological markers in the depressive patients.These results will be reported in the symposium of CINP,1990.