血管紧张肽(素)转化酶动力学测定方法的探讨及其初步临床应用

目的建立血管紧张肽(素)转化酶(ACE)自动化分析方法。方法 ACE能催化底物呋喃酰基-L-苯丙氨酰甘氨酰甘氨酸(FAPGG),产生呋喃酰基苯丙氨酸(FAP)及双甘氨肽(GG)。在pH值8.2的硼酸缓冲液下,在340 nm处测定产物吸光度值的下降速度可计算出ACE活性。采用本法测定50名正常对照者、30例慢性阻塞性肺部疾病加重期(AECOPD)患者、18例肺癌患者血清ACE的活性。结果本法缓冲液最适pH值为8.2,最适基质浓度为1.0 mmol/L,批内、批间平均变异系数(CV)分别为4.07%、5.50%,米氏常数(Km)为0.09 mmol/L。正常对照组ACE活性为(31.1±18.0)U/L;AECOPD患者ACE活性为(22.4±12.6)U/L,低于正常组(P<0.000 1);肺癌患者ACE活性为(28.7±11.4)U/L,稍低于正常对照组,但差异无统计学意义(P>0.05)。结论该法简便、快捷、精确,可用于自动化分析,适宜临床常规应用。ACE可作为评价肺部疾病的一项指标。

Investigation on kinetic monitoring of angiotensin converting enzyme and its preliminary clinical application

Objective To establish a kinetic monitoring assay for detecting angiotensin converting enzyme(ACE).Methods N-(32-Furyl]Acryloyl)-L-Phe-Gly-Gly(FAPGG) was used as substrate.ACE could catalyze the substrate to produce N-(32-Furyl]Acryloyl)-L-Phe(FAP) and glycine-glycine(GG) in boric acid-sodium hydroxide buffer(pH: 8.2).The activity of ACE could be calculated through determining the decreasing speed of the product at 340 nm.The ACE activities in 50 healthy controls,30 patients with acute exacerbation chroni...