Sunderman F W
Department of Laboratory Medicine, University of Connecticut Medical School, Farmington 06032.
Ann Clin Lab Sci. 1990 Mar-Apr;20(2):123-39.
This review delineates the subcellular distribution, biochemical characteristics, and metabolic functions of 5'-nucleotidase (5'NT), summarizes the analytical biochemistry of 5'NT, and assesses the clinical significance of 5'NT determinations in body fluids, cells, and tissues. Salient aspects of the clinical biochemistry of 5'NT, discussed herein, are as follows: (A) Serum 5'NT activity is generally elevated in hepatobiliary diseases, especially with intrahepatic obstruction, but, unlike serum alkaline phosphatase, serum 5'NT activity is not increased in infancy, childhood, pregnancy, or osteoblastic disorders. (B) In cancer patients, elevated serum 5'NT activity does not always indicate hepatobiliary involvement; in some cases, 5'NT may be released into serum from the primary tumor or local metastases. (C) Genetic deficiency of erythrocyte pyrimidine 5'NT activity is a common cause of hereditary non-spherocytic hemolytic anemia. (D) Acquired deficiency of erythrocyte pyrimidine 5'NT activity occurs in patients with beta-thalassemia and lead poisoning. (E) 5'NT activity is low in circulating monocytes, increases markedly upon their differentiation to tissue macrophages, and subsequently diminishes during macrophage activation. (F) Lymphocyte ecto-5'NT activity, a plasma membrane marker of cell maturation, is generally low in immunodeficiency states, and undergoes characteristic changes in patients with certain lymphomas and leukemias.
本综述阐述了5'-核苷酸酶（5'NT）的亚细胞分布、生化特性及代谢功能，总结了5'NT的分析生物化学，并评估了体液、细胞及组织中5'NT测定的临床意义。本文讨论的5'NT临床生物化学的显著方面如下：（A）肝胆疾病时血清5'NT活性通常升高，尤其是肝内梗阻时，但与血清碱性磷酸酶不同，婴儿期、儿童期、孕期或成骨细胞疾病时血清5'NT活性不升高。（B）癌症患者中，血清5'NT活性升高并不总是提示肝胆受累；在某些情况下，5'NT可能从原发性肿瘤或局部转移灶释放至血清中。（C）红细胞嘧啶5'NT活性的遗传性缺乏是遗传性非球形细胞溶血性贫血的常见原因。（D）β地中海贫血和铅中毒患者会出现红细胞嘧啶5'NT活性的获得性缺乏。（E）循环单核细胞中的5'NT活性较低，分化为组织巨噬细胞时显著增加，随后在巨噬细胞激活过程中降低。（F）淋巴细胞外5'NT活性是细胞成熟的质膜标志物，在免疫缺陷状态下通常较低，在某些淋巴瘤和白血病患者中会发生特征性变化。
