title: Low-renin (volume dependent) mild-hypertensive patients have impaired flow-mediated and glyceryl-trinitrate stimulated vascular reactivity.
abstract: BACKGROUND
  Low-renin (volume-dependent) hypertension represents 25-30% of all cases of primary hypertension. Endothelial dysfunction and vascular remodeling are associated with hypertension but their relevance to volume-dependent hypertension (VDH) is not yet known. To evaluate this, flow-mediated dilation (FMD) of the brachial artery and the carotid intima-media thickness in the distal common carotid artery were measured and compared between renin-dependent mild-hypertensive patients (RDH) and controls.
  
  
  RESULTS
  The study group comprised 40 mild-hypertensive patients and 25 controls. Plasma renin activity (PRA), plasma aldosterone concentration, angiotensin II and nitrite/nitrate plasma levels were measured. According to PRA, subjects were classified as VDH (<0.6 ng . ml (-1) . h(-1)), or RDH (>0.6 ng . ml(-1) . h (-1)). Vascular function was evaluated by FMD before and after reactive hyperemia (RH) and glyceryl-trinitrate (GTN) administration. FMD in response to RH and GTN in the VDH group when compared with RDH group was 10.2+/-2.8% vs 13.3+/-3.6% (p=0.01); and 16.0+/-3.5% vs 19.9+/-4.5% (p=0.01), respectively.
  
  
  CONCLUSIONS
  This study showed impaired FMD and reduced GTN response in mildly hypertensive patients with low-renin plasma levels.
authors.affiliation: Cardiovascular Pharmacology and Hypertension Section, Clinical Hospital of Campinas & Faculty of Medical Sciences, State University of Campinas (UNICAMP), Brazil.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Yugar-Toledo
authors.forename: Lúcia Helena
authors.initials: LH
authors.lastname: Bonalume Tácito
authors.forename: Sílvia Elaine
authors.initials: SE
authors.lastname: Ferreira-Melo
authors.forename: Walnéia
authors.initials: W
authors.lastname: Sousa
authors.forename: Fernanda
authors.initials: F
authors.lastname: Consolin-Colombo
authors.forename: Maria Cláudia
authors.initials: MC
authors.lastname: Irigoyen
authors.forename: Kléber
authors.initials: K
authors.lastname: Franchini
authors.forename: Otávio Rizzi
authors.initials: OR
authors.lastname: Coelho
authors.forename: Heitor
authors.initials: H
authors.lastname: Moreno
mesh_terms: D000328:Adult; D001916:Brachial Artery / Q000473:pathology / Q000503:physiopathology; D017536:Carotid Artery, Common / Q000473:pathology / Q000503:physiopathology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000008:administration & dosage*; D012083:Renin / Q000097:blood*; D017539:Tunica Intima / Q000473:pathology / Q000503:physiopathology*; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000008:administration & dosage*
chemical_list: D014665:Vasodilator Agents; D012083:Renin; D005996:Nitroglycerin