title: Differences in angiotensin convertase enzyme (ACE) activity and expression may contribute to shorter event free period after coronary artery bypass graft surgery.
abstract: OBJECTIVE
  The goal of this study was to investigate the importance of the vascular angiotensin convertase enzyme (ACE) in coronary artery bypass graft surgery (CABG) patients.
  
  
  METHODS
  Vascular tissue (distal saphenous vein [n= 163] and/or radial artery [n= 120] segments) and blood samples were collected from CABG patients (n= 81). We studied (i) the potency of angiotensin I (AngI) and angiotensin II (AngII) to evoke vascular contractions; (ii) vascular and plasma ACE concentrations; and (iii) ACE genotype of the patients enrolled.
  
  
  RESULTS
  The ratio of the potencies (EC(50) ) of AngII and AngI was significantly lower in radial artery compared to the saphenous vein (0.17 ± 0.03 nM and 0.51 ± 0.14 nM, respectively, P= 0.003), suggesting a 3-fold more effective AngI conversion in saphenous vein samples. Angiotensin constrictions were inhibited with telmisartan and captopril in both saphenous veins and radial arteries. Vascular ACE expression was significantly higher in saphenous vein compared to radial artery (9.7 ± 1.0 ng/mg and 5.3 ± 0.7 ng/mg, respectively, P= 0.01). Serum but no tissue ACE concentration was determined by ACE insertion/deletion polymorphism. Accordingly, no relation was found between serum and tissue ACE expression.
  
  
  CONCLUSIONS
  ACE-inhibitor therapy targeting tissue located ACE may be beneficial to patients with saphenous vein grafts after CABG surgery.
authors.affiliation: Institute of Cardiology, University of Debrecen, Debrecen, Hungary.
authors.forename: Andrea
authors.initials: A
authors.lastname: Daragó
authors.forename: Miklós
authors.initials: M
authors.lastname: Fagyas
authors.forename: Ivetta M
authors.initials: IM
authors.lastname: Siket
authors.forename: Andrea
authors.initials: A
authors.lastname: Facskó
authors.forename: Zita
authors.initials: Z
authors.lastname: Megyesi
authors.forename: Judit
authors.initials: J
authors.lastname: Kalász
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Galajda
authors.forename: Tamás
authors.initials: T
authors.lastname: Szerafin
authors.forename: Jolán
authors.initials: J
authors.lastname: Hársfalvi
authors.forename: István
authors.initials: I
authors.lastname: Edes
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Papp
authors.forename: Attila
authors.initials: A
authors.lastname: Tóth
authors.forename: József
authors.initials: J
authors.lastname: Szentmiklósi
mesh_terms: D000368:Aged; D047228:Angiotensin II Type 1 Receptor Blockers / Q000494:pharmacology; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D001026:Coronary Artery Bypass / Q000009:adverse effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D006814:Hungary; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D011183:Postoperative Complications / Q000097:blood / Q000201:enzymology / Q000209:etiology*; D011446:Prospective Studies; D017534:Radial Artery / Q000187:drug effects / Q000201:enzymology; D018570:Risk Assessment; D012307:Risk Factors; D012501:Saphenous Vein / Q000187:drug effects / Q000201:enzymology / Q000637:transplantation*; D013997:Time Factors; D016896:Treatment Outcome; D014662:Vasoconstrictor Agents / Q000494:pharmacology
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors; D014662:Vasoconstrictor Agents; D007703:Peptidyl-Dipeptidase A