神经管缺陷特异性乙酰胆碱酯酶：其特性及在无脑儿和脊柱裂检测中的定量分析

Neural tube defect-specific acetylcholinesterase: its properties and quantitation in the detection of anencephaly and spina bifida.

作者信息

Bonham J R, Dale G, Atack J R

机构信息

Department of Clinical Biochemistry, Newcastle General Hospital, Newcastle upon Tyne, UK.

出版信息

Clin Chim Acta. 1987 Nov 30;170(1):69-77. doi: 10.1016/0009-8981(87)90384-6.

DOI:10.1016/0009-8981(87)90384-6

PMID:2449304

Abstract

Amniotic fluid from neural tube defect-affected pregnancies (NTD) contains three forms of acetylcholinesterase (AChE), the major species of which is present only in trace amounts in normal pregnancies or those associated with a non-NTD fetal malformation. The activity of this 'specific' AChE is increased 62-fold in the presence of NTD and its measurement provides a sensitive and specific test for the biochemical detection of this disorder. The sedimentation coefficient of 'NTD specific' AChE (10.3S) indicates that it is a tetrameric species, and that the two additional forms present, (4.0S and 5.5S) are monomer and dimer, respectively. Gel filtration studies also support these findings. Combining these data, the molecular masses of monomer, dimer and tetramer are shown to be 78, 126 and 256 kDa (+/- 10%). 'NTD-Specific' AChE does not react with the detergent Triton X-100, indicating that it is a soluble, and probably secreted, species without membrane associating properties.

摘要

神经管缺陷（NTD）妊娠的羊水含有三种形式的乙酰胆碱酯酶（AChE），其中主要形式在正常妊娠或与非NTD胎儿畸形相关的妊娠中仅以痕量存在。在存在NTD的情况下，这种“特异性”AChE的活性增加了62倍，其测量为这种疾病的生化检测提供了一种灵敏且特异的测试。“NTD特异性”AChE的沉降系数（10.3S）表明它是一种四聚体形式，另外存在的两种形式（4.0S和5.5S）分别是单体和二聚体。凝胶过滤研究也支持这些发现。综合这些数据，单体、二聚体和四聚体的分子量分别为78、126和256 kDa（±10%）。“NTD特异性”AChE不与去污剂Triton X-100反应，表明它是一种可溶性的、可能分泌的形式，不具有膜结合特性。