›› 2010, Vol. 30 ›› Issue (2): 240-.

• Technique and method • Previous Articles     Next Articles

Synthesis of substrate for angiotensin-converting enzyme and its value in diagnosis of lung cancer

ZHOU Hai-yan1, YAO Li-yun2, LI Ying-yi3, ZHANG Jian-hua2   

  1. 1. Department of Clinical Laboratory, Shanghai Chest Hospital, Shanghai Jiaotong University, Shanghai 200030, China;2. Department of Chemistry, Basic Medical College, Shanghai Jiaotong University, Shanghai 200025, China;3. Office of Counselor, School of Medicine, Shanghai Jiaotong University, Shanghai 200025, China
  • Online:2010-02-25 Published:2010-02-25
  • Supported by:

    Shanghai Municipal Health Bureau Foundation, 2007085

Abstract:

Objective To establish the synthetic method of the substrate for angiotensin-converting enzyme (ACE), and investigate the assay method of serum ACE. Methods The substrate was prepared by the use of N-hydroxysuccinimide ester in peptide synthesis, and serum ACE was determined by spectrophotometric assay using substrate. Results The substrate of furanacryloyl-phenylalanyl-glycyl-glycine with purity of 99.5% was obtained. The Km value for the substrate was 0.25 mmol/L, the normal reference interval for serum ACE activity was 46.7 U/L to 113.3 U/L, and the within-run and between-run coefficient of variation (CVs) ranged from 3.9 to 4.9%. The serum ACE activity in patients with squamous carcinoma and adenocarcinoma of lung were significantly decreased (P<0.05), while that in patients with lung small cell carcinoma was not significantly decreased (P>0.05). Conclusion The synthesized substrate could be reliably used as a marker for diagnosis of different lung cancers in clinics.

Key words: angiotensin converting enzyme, furanacryloyl-phenylalanyl-glycyl-glycine, lung cancer