HUMAN HEPATIC MICROBODIES WITH CRYSTALLOID CORES
HUMAN HEPATIC MICROBODIES WITH CRYSTALLOID CORES
复制标题
具有晶体核心的人肝微生物
作者：
L. Biempica
Rouiller 和 Bernhard (1) 以及 Gansler 和 Rouiller (2) 于 1956 年首次描述了肝脏微体。在大鼠中，它们是圆形或椭圆形的物体，比线粒体稍小。它们由单位膜界定，并具有中等致密的基质和具有独特晶体排列的致密核心或核。 de Duve 和他的同事对大鼠肝脏和肾脏中的微生物进行了生化表征 (3, 4)。大鼠肝脏的密度梯度离心产生了含有大量微生物和高水平尿酸氧化酶（尿酸酶）、D-氨基酸氧化酶和 L-a-羟基酸氧化酶、形成过氧化氢的氧化酶和过氧化氢酶（一种破坏过氧化氢的酶）的级分。由于过氧化氢是这些酶的产物或底物，因此最近提出了术语“过氧化物酶体”来形容这些颗粒 (5)。尿酸氧化酶纯化 80 倍的制剂含有大量游离晶体核心 (4)。这些观察结果表明，D-氨基酸氧化酶和过氧化氢酶存在于基质中，并且尿酸氧化酶存在于核心中。大鼠肾微体没有可检测到的尿酸氧化酶活性 (3)。有趣的是，在已发表的电子显微照片中，正如我们自己的研究一样，大鼠肾脏微体具有中心密度，但没有晶体结构（参见参考文献 6 中的图 10）。尽管鱼类、两栖动物和大多数哺乳动物表现出尿酸氧化酶活性，但灵长类动物（包括人类）、鸟类和大多数爬行动物缺乏这种酶。人和鸡肝脏中不存在尿酸氧化酶，这与电子显微镜检查的标本中不存在类核是一致的 (7)。该报告描述了人类肝脏活检标本中存在含有晶体的微体。
Hepatic microbodies were first described in 1956 by Rouiller and Bernhard (1) and by Gansler and Rouiller (2). In the rat, they are round or oval bodies that are somewhat smaller than mitochondria. They are delimited by a unit membrane and possess a moderately dense matrix and a dense core or nucleoid with a distinctive crystalloid arrangement. Microbodies have been characterized biochemically in rat liver and kidney by de Duve and his colleagues (3, 4). Density gradient centrifugation of rat liver has yielded fractions with numerous microbodies and high levels of urate oxidase (uricase), D-amino acid oxidase, and L-a-hydroxy acid oxidase, oxidases that form hydrogen peroxide, and catalase, an enzyme that destroys hydrogen peroxide. Because hydrogen peroxide is either the product or substrate of these enzymes, the term "peroxisome" has recently been proposed for these particles (5). A preparation with an 80-fold purification of urate oxidase contains a great number of free crystalloid cores (4). These observations suggest that D-amino acid oxidase and catalase are present in the matr ix and that urate oxidase is present in the core. Ra t kidney microbodies have no detectable urate oxidase activity (3). I t is of interest that in published electron micrographs, as in our own studies, rat kidney microbodies have central densities but no crystalloid structures (see Fig. 10 in reference 6). Although fish, amphibia, and most mammals exhibit urate oxidase activity, primates (including man), birds, and most reptiles lack this enzyme. The absence of urate oxidase in human and chick liver is consistent with the absence of the nucleoid in specimens examined in the electron microscope (7). This report describes the presence of crystalloidcontaining microbodies in a biopsy specimen of human liver.