title: Metabolic syndrome and endothelin-1 mediated vasoconstrictor tone in overweight/obese adults.
abstract: OBJECTIVE
  To determine whether endothelin (ET)-1 vasoconstrictor tone is greater in overweight and obese adults with the metabolic syndrome (MetS).
  
  
  METHODS
  Forty overweight/obese middle-aged and older adults (age: 43-71 years; BMI: 25.1-36.9 kg/m²) were studied: 20 without MetS (13 M/7 F) and 20 with MetS (13 M/7 F). MetS was established according to NCEP ATP III guidelines. Forearm blood flow (FBF; plethysmography) responses to intra-arterial infusion of selective ET(A) receptor blockade (BQ-123; 100 nmol/min; for 60 min) and non-selective ET(A/B) receptor blockade (BQ-123 + BQ-788 [50 nmol/min for 60 min]) were determined.
  
  
  RESULTS
  In response to the selective ET(A) antagonism, there was a significant increase in forearm blood flow from baseline in both groups. However, the increase in forearm blood flow was significantly higher (P=0.03; ~45%) in the overweight/obese group with MetS than the group without MetS. In contrast, there were no significant group differences in FBF responses to non-selective ET(A/B) receptor blockade. Peak vasodilator responses to nonselective ET(A/B) blockade were ~50% higher than baseline blood flow in the overweight/obese groups without and with MetS.
  
  
  CONCLUSIONS
  MetS is associated with higher ET-1 vasoconstrictor tone in overweight/obese adults. The enhanced ET-1 vasoconstrictor activity with MetS is mediated by the ET(A) receptor subtype.
authors.affiliation: Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309; Department of Physiology and Pharmacology, Fluminense Federal University, Niteroi, RJ, 24210-130.
authors.forename: Natalia G
authors.initials: NG
authors.lastname: Rocha
authors.affiliation: Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309.
authors.forename: Danielle L
authors.initials: DL
authors.lastname: Templeton
authors.affiliation: Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309.
authors.forename: Jared J
authors.initials: JJ
authors.lastname: Greiner
authors.affiliation: Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309; Department of Medicine, University of Colorado Denver and the Health Sciences Center, Aurora, CO 80045; Denver Health Medical Center, Denver, CO 80204.
authors.forename: Brian L
authors.initials: BL
authors.lastname: Stauffer
authors.affiliation: Integrative Vascular Biology Laboratory, Department of Integrative Physiology, University of Colorado, Boulder, CO 80309; Department of Medicine, University of Colorado Denver and the Health Sciences Center, Aurora, CO 80045. Electronic address: desouzac@colorado.edu.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: DeSouza
mesh_terms: D000328:Adult; D000368:Aged; D001808:Blood Vessels / Q000187:drug effects / Q000503:physiopathology*; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D065130:Endothelin A Receptor Antagonists; D065131:Endothelin B Receptor Antagonists; D019332:Endothelin-1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005260:Female; D005542:Forearm; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000378:metabolism / Q000503:physiopathology*; D008875:Middle Aged; D009765:Obesity / Q000150:complications; D050177:Overweight / Q000150:complications*; D058246:Prehypertension / Q000175:diagnosis / Q000209:etiology*; D044022:Receptor, Endothelin A / Q000378:metabolism*; D044023:Receptor, Endothelin B / Q000378:metabolism; D012039:Regional Blood Flow / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects; D014661:Vasoconstriction / Q000187:drug effects; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents
chemical_list: D065130:Endothelin A Receptor Antagonists; D065131:Endothelin B Receptor Antagonists; D019332:Endothelin-1; D044022:Receptor, Endothelin A; D044023:Receptor, Endothelin B; D014665:Vasodilator Agents
keywords: Blood flow; Endothelin-1; Metabolic syndrome