Murphy D L, Redmond D E, Garrick N, Baulu J
Neurochem Res. 1979 Feb;4(1):53-62. doi: 10.1007/BF00963831.
Monoamine oxidase in the vervet monkey showed greater variations in activity in six brain regions when tyramine or phenylethylamine was used as the substrate (3.8- to 4.1-fold differences) than when serotonin was the substrate (1.8-fold differences). With phenylethylamine and tyramine as substrates, the highest MAO specific activities were found in the hypothalamus and the lowest in the cerebellum and cortex. With serotonin as the substrate, the highest specific activities were in the mesencephalon and cortex. The inhibition of tyramine deamination by clorgyline and deprenyl yielded biphasic plots indicative of the presence of MAO-A and MAO-B enzyme forms in the vervet brain. On the basis of these inhibitor curves, the vervet brain could be estimated to contain approximately 85% MAO-B and 15% MAO-A, in contrast to rat brain which contains 45% MAO-B and 5% MAO-A. The inhibition of serotonin deamination by deprenyl in vervet brain yielded a biphasic plot, suggesting that some serotonin deamination in the vervet is accomplished by the MAO-B enzyme form. Estimations of the relative amounts of MAO-A and MAO-B based on inhibitor curves or based on substrate ratios yielded proportionate results which were in close agreement across the different brain regions, supporting the validity of these approaches to estimating MAO-A and MAO-B activities.
当以酪胺或苯乙胺为底物时，黑长尾猴大脑六个区域中的单胺氧化酶活性变化（差异为3.8至4.1倍）比以血清素为底物时（差异为1.8倍）更大。以苯乙胺和酪胺为底物时，单胺氧化酶的比活性在下丘脑最高，在小脑和皮质最低。以血清素为底物时，比活性最高的是中脑和皮质。氯吉兰和司来吉兰对酪胺脱氨基的抑制产生了双相图，表明黑长尾猴大脑中存在单胺氧化酶A和单胺氧化酶B两种酶形式。根据这些抑制剂曲线估计，黑长尾猴大脑中约含85%的单胺氧化酶B和15%的单胺氧化酶A，而大鼠大脑中含45%的单胺氧化酶B和5%的单胺氧化酶A。司来吉兰对黑长尾猴大脑中血清素脱氨基的抑制产生了双相图，表明黑长尾猴大脑中的一些血清素脱氨基是由单胺氧化酶B酶形式完成的。基于抑制剂曲线或底物比率对单胺氧化酶A和单胺氧化酶B相对含量的估计得出了成比例的结果，这些结果在不同脑区之间密切一致，支持了这些估计单胺氧化酶A和单胺氧化酶B活性方法的有效性。
