Pollow K, Sinnecker G, Boquoi E, Pollow B
J Clin Chem Clin Biochem. 1978 Sep;16(9):493-502. doi: 10.1515/cclm.1978.16.9.493.
The specific activity of 17beta-hydroxysteroid dehydrogenase was measured in normal human myometrium, and in leiomyoma specimens obtained from the same tumor-bearing uterus. In all cases the normal tissue showed greater conversion of estradiol-17beta into estrone than the neoplastic tissues. In normal myometrium of fertile women, the specific enzyme activity depended on the phase of the menstrual cycle, the highest values of 17beta-hydroxysteroid dehydrogenase activity being found in the early secretory phase. To determine the intracellular distribution of the 17beta-hydroxysteroid dehydrogenase, purified microsomes, mitochondria, nuclei and cytosol fractions were prepared. The purity of each fraction was monitored by marker enzymes. It was found that the enzyme was mainly located in mitochondria and microsomes. Furthermore it was demonstrated that the microsomal enzyme was bound tightly to the membranes of the endoplasmic reticulum, while the mitochondrial 17beta-hydroxysteroid dehydrogenase was mainly associated with the outer membranes of the organelle. Kinetic parameters (Km-values, coenzyme requirements, temperature and pH-optima) of the cytoplasmic, nuclear, mitochondrial and microsomal enzyme of normal and neoplastic tissue were compared.
在正常人体子宫肌层以及取自同一患瘤子宫的平滑肌瘤标本中测定了17β-羟基类固醇脱氢酶的比活性。在所有病例中，正常组织将雌二醇-17β转化为雌酮的能力均高于肿瘤组织。在育龄妇女的正常子宫肌层中，该特异性酶活性取决于月经周期阶段，在分泌期早期发现17β-羟基类固醇脱氢酶活性的最高值。为了确定17β-羟基类固醇脱氢酶的细胞内分布，制备了纯化的微粒体、线粒体、细胞核和胞质溶胶组分。通过标记酶监测各组分的纯度。发现该酶主要位于线粒体和微粒体中。此外还证明，微粒体酶紧密结合在内质网的膜上，而线粒体17β-羟基类固醇脱氢酶主要与该细胞器的外膜相关。比较了正常组织和肿瘤组织的细胞质、细胞核、线粒体和微粒体酶的动力学参数（Km值、辅酶需求、温度和最适pH）。
