Riederer P, Konradi C, Schay V, Kienzl E, Birkmayer G, Danielczyk W, Sofic E, Youdim M B
Adv Neurol. 1987;45:111-8.
The discovery that MAO can be differentiated biochemically and pharmacologically into two forms, types A and B, with different substrate specificities and inhibitor sensitivities has renewed the interest in MAO inhibiting as a therapeutic agent. L-Deprenyl, a selective inhibitor of MAO-B, was introduced by us into clinical use as an adjunct to L-DOPA some years ago. This drug has found therapeutic importance in that it can potentiate the pharmacological action of L-DOPA. The mechanism underlying the action of L-deprenyl is thought to be related to its inhibition of MAO-B and thus increased levels of PEA and DA, as measured in the striatal and limbic region of human brain. Animal studies have indicated the MAO-A is mainly, but not exclusively, located in brain neurons, while MAO-B is preferentially placed in glia and astrocytes. In general human and primate brain studies show similar MAO distribution. The observation that MAO-B activity could not be located in the catecholaminergic neurons of human brain by the use of monoclonal antibody studies seriously questions the validity of this technique. The exact locations of MAO-A and -B in human brain are important to understand the mechanism of L-deprenyl action as an antiparkinson drug. If there is an absence of MAO-B from dopaminergic neurons, one may now consider that MAO-B activity within glia plays a far more important role than hitherto considered. This, however, is questionable.
单胺氧化酶（MAO）可在生化和药理学上分为两种形式，即A 型和B型，它们具有不同的底物特异性和抑制剂敏感性，这一发现重新激发了人们对MAO抑制剂作为治疗药物的兴趣。几年前，我们将MAO - B的选择性抑制剂L - 司来吉兰作为左旋多巴（L - DOPA）的辅助药物引入临床应用。这种药物已显示出治疗重要性，因为它可以增强L - DOPA的药理作用。L - 司来吉兰作用的潜在机制被认为与其对MAO - B的抑制作用有关，从而使人类脑纹状体和边缘区域中测得的去甲肾上腺素（PEA）和多巴胺（DA）水平升高。动物研究表明，MAO - A主要（但并非唯一）位于脑神经元中，而MAO - B则优先存在于神经胶质细胞和星形胶质细胞中。一般来说，人类和灵长类动物脑研究显示出相似的MAO分布。通过单克隆抗体研究发现无法在人类脑的儿茶酚胺能神经元中定位MAO - B活性，这严重质疑了该技术的有效性。了解MAO - A和 - B在人类脑中的确切位置对于理解L - 司来吉兰作为抗帕金森病药物的作用机制很重要。如果多巴胺能神经元中不存在MAO - B，那么现在人们可能会认为神经胶质细胞内的MAO - B活性所起的作用比迄今所认为的要重要得多。然而，这一点是值得怀疑的。
