Ichikawa K, Hashizume K, Yamada T
Endocrinology. 1982 Dec;111(6):1803-9. doi: 10.1210/endo-111-6-1803.
Inhibitory modulators of monoamine oxidase (MAO) were found in rat heart 105,000 X g supernatant. The modulators inhibited MAO activity present in the outer mitochondrial membrane. The inhibition was noncompetitive when using membrane-associated MAO as enzyme source. The modulators did not, however, inhibit the enzyme activity in the soluble fraction prepared from outer mitochondrial membranes. MAO inhibitory modulator concentration in rat heart cytosol was increased by the administration of T4 to rats. Three different inhibitory molecules were identified by gel filtration studies. These results suggest that thyroid hormone regulates membrane-associated MAO activity via the production of MAO inhibitory modulators, that the modulators probably bind to specific sites on the outer mitochondrial membrane, and that this binding of modulators to the membranes may result in a structural change in the mitochondrial membrane and a decrease in MAO enzyme activity.
在大鼠心脏105,000 X g上清液中发现了单胺氧化酶（MAO）的抑制性调节剂。这些调节剂抑制线粒体外膜中存在的MAO活性。当使用膜相关MAO作为酶源时，这种抑制是非竞争性的。然而，这些调节剂并不抑制从线粒体外膜制备的可溶性部分中的酶活性。给大鼠注射T4后，大鼠心脏胞质溶胶中MAO抑制性调节剂的浓度增加。通过凝胶过滤研究鉴定出三种不同的抑制性分子。这些结果表明，甲状腺激素通过产生MAO抑制性调节剂来调节膜相关MAO活性，这些调节剂可能与线粒体外膜上的特定位点结合，并且调节剂与膜的这种结合可能导致线粒体膜的结构变化和MAO酶活性的降低。
