Wolvekamp M C, de Bruin R W
Department of Pediatric Surgery, Erasmus University, Rotterdam, The Netherlands.
Dig Dis. 1994 Jan-Feb;12(1):2-14. doi: 10.1159/000171432.
This article is a review of the historical, biochemical, and functional aspects of the enzyme diamine oxidase (DAO). The amine oxidase DAO, formerly called histaminase, is found in various tissues, but is especially active in the intestinal mucosa. Its function is the oxidative deaminating of several polyamines, essential substances for cell proliferation. DAO is thus a regulating enzyme in rapidly proliferating tissues such a bone marrow and intestinal mucosa. Results from several studies have demonstrated that both ornithine decarboxylase (ODC) and DAO activity rise during adaptive hyperplasia seen after small bowel resection. The ODC-dependent increase in polyamine content and subsequent increase in cell proliferative activity is probably downregulated locally in the villus tip by the increased DAO activity. DAO is normally present in very small amounts in the circulation and its basal plasma levels are positively correlated with the maturity and integrity of the intestinal mucosa. After intravenous administration of heparin, DAO is released from its capillary binding sites in the lamina propria into the peripheral circulation. Measurement of postheparin DAO release enhances its sensitivity and is now extensively studied to assess its value as follow-up or screening test for several enteropathies. Measuring basal as well as postheparin DAO levels has potential relevance following small bowel transplantation. Rejection of the small bowel graft leads to mucosal damage, which could conceivably lead to changes in DAO activity.
本文是对二胺氧化酶（DAO）的历史、生化及功能方面的综述。胺氧化酶DAO，以前称为组胺酶，存在于多种组织中，但在肠黏膜中活性尤其高。其功能是对几种多胺进行氧化脱氨，多胺是细胞增殖所必需的物质。因此，DAO是骨髓和肠黏膜等快速增殖组织中的一种调节酶。多项研究结果表明，在小肠切除术后出现的适应性增生过程中，鸟氨酸脱羧酶（ODC）和DAO的活性均会升高。多胺含量依赖ODC的增加以及随后细胞增殖活性的增加，可能在绒毛顶端因DAO活性增加而受到局部下调。DAO在循环中通常含量极少，其基础血浆水平与肠黏膜的成熟度和完整性呈正相关。静脉注射肝素后，DAO从固有层的毛细血管结合位点释放到外周循环中。测定肝素后DAO的释放可提高其敏感性，目前已对其进行广泛研究，以评估其作为多种肠道疾病随访或筛查试验的价值。在小肠移植后，测定基础及肝素后DAO水平可能具有相关性。小肠移植物的排斥会导致黏膜损伤，这可能会导致DAO活性发生变化。
