Strolin Benedetti M, Eschalier A, Lesage A, Dordain G, Rovei V, Zarifian E, Dostert P
Eur J Clin Pharmacol. 1984;26(1):71-7. doi: 10.1007/BF00546712.
Prolactin (PRL) secretion is stimulated by serotonin (5-HT) and inhibited by dopamine (DA). 5-HT is generally recognized as a substrate for type A monoamine oxidase (MAO), whereas DA is considered as a substrate for either A or B, or both forms of MAO, depending on the species and tissues used. The effect of cimoxatone, a reversible, selective MAO-A inhibitor, on diurnal variation in plasma PRL level was investigated in healthy adults after a single 40 mg oral dose, as an indirect approach to investigating whether DA is preferentially a substrate for Type A or B MAO in man. The circadian rhythm in PRL, stress conditions and diet were taken into account in the present study, which was placebo-controlled. There was a slight but significant reduction in circulating PRL in the six subjects, which persisted for at least 9 h after cimoxatone. However, the duration of the decrease in plasma PRL was shorter than the inhibition of MAO-A. The results are not inconsistent with the presence of both forms of MAO in the human hypothalamus and with DA as a substrate for both forms in this region, if it is assumed that the hypothalamic concentrations of the drug during the period 0-9 hours was sufficiently high to inhibit DA deamination by both forms of MAO.
催乳素（PRL）的分泌受血清素（5-羟色胺，5-HT）刺激，受多巴胺（DA）抑制。5-羟色胺通常被认为是A型单胺氧化酶（MAO）的底物，而多巴胺则根据所使用的物种和组织，被认为是A型或B型单胺氧化酶，或两种形式单胺氧化酶的底物。作为一种间接方法，用于研究在人类中多巴胺是否优先作为A型或B型单胺氧化酶的底物，在健康成年人单次口服40毫克剂量后，研究了一种可逆的、选择性MAO-A抑制剂西莫沙酮对血浆PRL水平昼夜变化的影响。本研究为安慰剂对照研究，考虑了PRL的昼夜节律、应激条件和饮食因素。六名受试者的循环PRL略有但显著降低，在服用西莫沙酮后至少持续9小时。然而，血浆PRL降低的持续时间短于MAO-A的抑制时间。如果假设在0至9小时期间下丘脑的药物浓度足够高，足以抑制两种形式单胺氧化酶对多巴胺的脱氨作用，那么这些结果与人类下丘脑同时存在两种形式的单胺氧化酶以及多巴胺作为该区域两种形式单胺氧化酶的底物是一致的。
