Garpenstrand H, Ekblom J, Forslund K, Rylander G, Oreland L
Department of Neuroscience, Uppsala University, Sweden.
J Neural Transm (Vienna). 2000;107(5):523-30. doi: 10.1007/s007020070075.
Monoamine oxidases (MAO) play a critical role in the degradation of endogenous and exogenous amines throughout the body. There are two distinct MAO isoforms, MAO-A and MAO-B, which both are encoded in genes on the X chromosome. Alterations in MAO-B activity have previously been connected with several neurological disorders. Platelet MAO (trbc-MAO) is exclusively of the B-type and the catalytic activity of this enzyme is under strong, yet unknown, genetic control. Specific trbc-MAO activity has been reported to be increased in certain neurodegenerative diseases and to correlate with personality traits such as sensation seeking and impulsiveness. In the present study, we investigated if trbc-MAO activity is associated with genotype at a variable region (A/G dimorphism) in intron 13 of the human gene encoding MAO-B. The MAOB intron 13 allele status and levels of trbc-MAO were determined for 55 Caucasian non-smoking males. Individuals with the "A-allele" displayed significantly lower enzyme activity than individuals with the "G-allele", i.e. 11.4 +/- 0.6 nmol/10(10) platelets/min compared with 13.5 +/- 0.6 (mean +/- SEM, p = 0.019). The present results suggest that the MAOB genotype may be involved in determining trbc-MAO activity.
单胺氧化酶（MAO）在全身内源性和外源性胺类的降解过程中起着关键作用。存在两种不同的MAO亚型，即MAO - A和MAO - B，它们均由X染色体上的基因编码。先前已发现MAO - B活性的改变与多种神经疾病有关。血小板MAO（trbc - MAO）仅为B型，且该酶的催化活性受强大但未知的基因控制。据报道，在某些神经退行性疾病中，特定的trbc - MAO活性会升高，并且与诸如寻求刺激和冲动等人格特质相关。在本研究中，我们调查了trbc - MAO活性是否与人类MAO - B编码基因第13内含子可变区（A / G二态性）的基因型相关。测定了55名白种非吸烟男性的MAOB第13内含子等位基因状态和trbc - MAO水平。携带“A等位基因”的个体显示出的酶活性显著低于携带“G等位基因”的个体，即分别为11.4±0.6 nmol / 10（10）血小板/分钟和13.5±0.6（平均值±标准误，p = 0.019）。目前的结果表明，MAOB基因型可能参与决定trbc - MAO活性。
