Angiotensin I converting enzyme (kininase II) of the brush border of human and swine intestine.
Angiotensin I converting enzyme (kininase II) of the brush border of human and swine intestine.
复制标题
人和猪肠道刷状缘的血管紧张素 I 转换酶（激肽酶 II）。
DOI：
10.1016/0006-2952(80)90603-6
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发表时间：
1980
影响因子：
5.8
通讯作者：
E. G. Erdös
中科院分区：
文献类型：
--
作者：
P. Ward;M. Sheridan;Katy J. Hammon;E. G. Erdös
人和猪小肠粘膜刷状缘富含血管紧张素转换酶（ACE）。通过在不连续甘油梯度上离心纯化肠粘膜的刷状缘。透射电子显微镜照片显示，90%的孤立囊泡具有三层膜结构和糖萼，肠刷状缘的特征。没有明显的其他亚细胞颗粒污染。在最终纯化的制剂中，刷状缘标记酶蔗糖酶、海藻糖酶和碱性磷酸酶从人肠中富集23倍、18倍和17倍，从猪组织中富集27倍、26倍和20倍。ACE高度集中在人类和猪的灌木丛边界。ACE在人类和猪刷状缘馏分的比活性富集17和7.6倍以上的粗匀浆。生物测定法显示了激肽酶活性。口服活性的ACE特异性抑制剂Captopril可抑制该酶，其I50为3 × 10−9。猪肾ACE抗体与猪小肠ACE发生交叉反应，表明猪肾ACE抗体与猪小肠ACE抗体具有共同的抗原决定簇，且酶主要集中在刷状缘膜上。由于肠道中存在大量ACE，因此长期服用巯甲丙脯酸可能会干扰这种酶的功能。
Mucosal brush border of human and swine small intestine is rich in angiotensin I converting enzyme or kininase II (ACE). The brush border of the intestinal mucosa was purified by centrifugation over a discontinuous glycerol gradient. Transmission electron micrographs showed that 90 per cent of the isolated vesicles had a trilaminar membrane structure and glycocalyx, characteristic of intestinal brush border. No significant contamination by other subcellular particles was evident. In the final purified preparation, the brush border marker enzymes sucrase, trehalase and alkaline phosphatase were enriched 23-, 18- and 17-fold from human intestine and 27-, 26- and 20-fold from swine tissue. ACE was highly concentrated in the human and swine brush border. The specific activity of ACE in the human and swine brush border fractions was enriched 17- and 7.6-fold over the crude homogenate. Kininase activity was demonstrated by bioassay. Captopril, the orally active specific inhibitor of ACE, inhibited the enzyme; its I50was 3 × 10−9. Antibody to swine kidney ACE cross-reacted with swine intestinal enzyme as shown in rocket immunoelectrophoresis, indicating that the enzymes from kidney and from intestine have common antigenic determinants and that the enzyme is concentrated on the brush border membrane. Because of the abundant presence of ACE in the intestine, interference in the functions of this enzyme may occur with chronic captopril therapy.