title: Increased expression of peripheral benzodiazepine receptors on leukocytes in silent myocardial ischemia.
abstract: OBJECTIVE
  The purpose of this study was to evaluate benzodiazepine receptor expression on leukocytes from patients with symptomatic or silent myocardial ischemia.
  
  
  BACKGROUND
  Silent myocardial ischemia is frequently observed in patients with coronary artery disease. Pain can be effectively controlled by various endogenous mechanisms. Benzodiazepines and their receptors play key roles in pain, in interactions with peptide opioids, in inflammation and in the response to stress.
  
  
  METHODS
  The study group consisted of 57 patients with reproducible exercise-induced myocardial ischemia. The presence of a constant behavior in the anginal pain perception during both exercise-induced ischemia and daily life was the most important inclusion criterion. Venous blood samples were taken from all patients to evaluate the expression of peripheral benzodiazepine receptors by flow cytometry. The study cohort was classified into two groups: 24 patients who had anginal pain both at home and during the exercise stress test and 33 patients who were asymptomatic during both daily life and exercise-induced ischemia.
  
  
  RESULTS
  Flow cytometry analysis showed increased expression of peripheral benzodiazepine receptors on all types of leukocytes in the asymptomatic patients. The difference was statistically significant for lymphocytes (p < 0.005), monocytes (p < 0.001) and granulocytes (p < 0.001).
  
  
  CONCLUSIONS
  These data show that expression of peripheral benzodiazepine receptors was higher in patients with silent myocardial ischemia than in symptomatic patients.
authors.affiliation: Department of Internal Medicine and Nephrology, IRCCS, San Matteo Hospital, University of Pavia, Italy. a.mazzone@smatteo.pv.it
authors.forename: A
authors.initials: A
authors.lastname: Mazzone
authors.forename: I
authors.initials: I
authors.lastname: Mazzucchelli
authors.forename: M
authors.initials: M
authors.lastname: Vezzoli
authors.forename: E
authors.initials: E
authors.lastname: Ottini
authors.forename: C
authors.initials: C
authors.lastname: Auguadro
authors.forename: A
authors.initials: A
authors.lastname: Serio
authors.forename: C
authors.initials: C
authors.lastname: Falcone
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000787:Angina Pectoris / Q000209:etiology / Q000503:physiopathology; D015331:Cohort Studies; D015444:Exercise; D005080:Exercise Test; D005260:Female; D005434:Flow Cytometry; D006098:Granulocytes / Q000378:metabolism; D006801:Humans; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D009203:Myocardial Infarction / Q000097:blood* / Q000503:physiopathology; D011963:Receptors, GABA-A / Q000097:blood*
chemical_list: D011963:Receptors, GABA-A