title: Hemodynamic consequences of neuropeptide Y-induced obesity.
abstract: BACKGROUND
  Acute central nervous system administration of neuropeptide Y (NPY) elicits variable hemodynamic responses. Chronic intracerebroventricular (ICV) administration of NPY produces obesity in rats. Obesity has been shown to increase arterial pressure.
  
  
  METHODS
  In this study we examined the chronic hemodynamic effects of NPY-induced obesity. Sprague-Dawley rats were implanted with radiotelemetry transmitters to continuously record heart rate and arterial pressure in the conscious state. Neuropeptide Y or vehicle was delivered into the third cerebral ventricle by osmotic minipumps over 2 weeks. Three groups were studied: vehicle, NPY-treated (free-fed), and NPY-treated (pair-fed to vehicle-treated rats).
  
  
  RESULTS
  Neuropeptide Y increased food intake and body weight in free-fed animals, and substantially augmented visceral adiposity in both free- and pair-fed rats. Despite increased adiposity, chronic ICV administration of NPY in conscious unstressed rats did not increase arterial pressure. Neuropeptide Y decreased heart rate, suggesting a sympathoinhibitory effect.
  
  
  CONCLUSIONS
  Obesity induced by 2-week ICV administration of NPY does not increase arterial pressure, perhaps indicating inhibition of sympathetic outflow that may oppose the pressor effect of adiposity.
authors.affiliation: Specialized Center of Research in Hypertension Genetics, Department of Internal Medicine, University of Iowa, Iowa City 52242, USA.
authors.forename: Marcelo L G
authors.initials: ML
authors.lastname: Correia
authors.forename: Donald A
authors.initials: DA
authors.lastname: Morgan
authors.forename: William I
authors.initials: WI
authors.lastname: Sivitz
authors.forename: Allyn L
authors.initials: AL
authors.lastname: Mark
authors.forename: William G
authors.initials: WG
authors.lastname: Haynes
mesh_terms: D000273:Adipose Tissue / Q000473:pathology; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D004435:Eating / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics; D007276:Injections, Intraventricular; D008297:Male; D009478:Neuropeptide Y / Q000008:administration & dosage / Q000494:pharmacology; D009765:Obesity / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014781:Viscera
chemical_list: D009478:Neuropeptide Y