Grosso D S, Gawienowski A M
J Endocrinol. 1975 May;65(2):207-14. doi: 10.1677/joe.0.0650207.
The monoamine oxidase (MAO) activity in the ovariectomized rat uterus was significantly increased above control levels in animals given testosterone: 33% (P smaller than 0.01) with tryptamine or 34% (P smaller than 0.05) with tyramine as substrate. Activity was also higher in hydrocortisone-treated animals: 30% (P smaller than 0.05) with tyramine or 25% (P smaller than 0.05) with tryptamine as substrate. Progesterone injection increased MAO activity toward tyramine by 20% but towards tryptamine by only 8%. The differences are not statistically significant but are believed to be real since they were reproducible. MAO activity in oestradiol-treated animals was 11% less than in the controls for both substrates. Although they are not significant differences, they were reproducible. No change in MAO activity was observed in the cerebellum, hypothalamus or anterior pituitary of ovariectomized rats after steroid treatment. At oestrus the enzyme activity in the uterus was lower than at dioestrus or prooestrus when beta-phenylethylamine was the substrate. When 5-hydroxytryptamine was used to measure enzyme activity, the same values were found at oestrus, dioestrus and prooestrus. Ovariectomy did not cause any changes in MAO activity in any of the tissues. Effects of the steroids in vivo were probably not due to a direct action on the enzyme since only at high concentration did they have any effect on the mitochondrial enzyme activity of the uterus in vivo.
给去卵巢大鼠注射睾酮后，其子宫中的单胺氧化酶（MAO）活性显著高于对照水平：以色胺为底物时升高33%（P小于0.01），以酪胺为底物时升高34%（P小于0.05）。氢化可的松处理的动物中MAO活性也较高：以酪胺为底物时升高30%（P小于0.05），以色胺为底物时升高25%（P小于0.05）。注射孕酮使MAO对酪胺的活性增加20%，但对色胺的活性仅增加8%。这些差异无统计学意义，但因其具有可重复性，故被认为是真实存在的。用两种底物时，经雌二醇处理的动物中MAO活性比对照低11%。虽然这些差异不显著，但具有可重复性。类固醇处理后，去卵巢大鼠的小脑、下丘脑或垂体前叶中未观察到MAO活性变化。发情期时，以β-苯乙胺为底物时子宫中的酶活性低于间情期或发情前期。以5-羟色胺测定酶活性时，发情期、间情期和发情前期的酶活性值相同。去卵巢未引起任何组织中MAO活性的变化。类固醇在体内的作用可能并非直接作用于该酶，因为只有在高浓度时它们才对子宫线粒体酶活性有体内效应。
