title: Antihypertensive treatment improves microvascular rarefaction and reactivity in low-risk hypertensive individuals.
abstract: OBJECTIVE
  To test whether long-term antihypertensive treatment with metoprolol succinate (a β₁-adrenoceptor blocker) or olmesartan medoxomil (an angiotensin II AT₁-receptor blocker) reverses microvascular dysfunction in hypertensive patients.
  
  
  METHODS
  This study included 44 hypertensive outpatients and 20 age and sex-matched healthy controls. We used skin capillaroscopy to measure capillary density and recruitment at rest and during PORH. Endothelium-dependent vasodilation of skin microcirculation was evaluated with a LDPM system in combination with ACh iontophoresis, PORH, and LTH.
  
  
  RESULTS
  Pretreatment capillary density in hypertensive patients was significantly reduced compared with controls (71.3 ± 1.5 vs. 80.6 ± 1.8 cap/mm²; p < 0.001), as was PORH (71.7 ± 1.5 vs. 79.5 ± 2.6 cap/mm²; p < 0.05). After treatment for six months, capillary density increased to 75.4 ± 1.1 cap/mm² (p < 0.01) at rest and 76.8 ± 1.1 cap/mm² during PORH. During LTH, CVC in perfusion units (PU)/mmHg was similar in patients (1.71 [1.31-2.12]) and controls (1.60 [1.12-1.91]) and increased significantly (1.82 [1.30-2.20]) after treatment. Maximal CVC during PORH was reduced in hypertensive patients (0.30 [0.22-0.39]) compared to controls (0.39 [0.31-0.49], p < 0.001) and increased (0.41 [0.29-0.51], p < 0.001) after treatment.
  
  
  CONCLUSIONS
  Capillary rarefaction and microvascular endothelial dysfunction in hypertensive patients responded favorably to long-term pharmacological treatment.
authors.affiliation: Clinical and Experimental Pathophysiology Unit, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Sérgio E
authors.initials: SE
authors.lastname: Kaiser
authors.forename: Antonio F
authors.initials: AF
authors.lastname: Sanjuliani
authors.forename: Vanessa
authors.initials: V
authors.lastname: Estato
authors.forename: Marilia B
authors.initials: MB
authors.lastname: Gomes
authors.forename: Eduardo
authors.initials: E
authors.lastname: Tibiriçá
mesh_terms: D058671:Adrenergic beta-1 Receptor Antagonists / Q000008:administration & dosage*; D000328:Adult; D047228:Angiotensin II Type 1 Receptor Blockers / Q000008:administration & dosage*; D002196:Capillaries / Q000503:physiopathology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000503:physiopathology; D007093:Imidazoles / Q000008:administration & dosage*; D008297:Male; D008790:Metoprolol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D008833:Microcirculation / Q000187:drug effects*; D008875:Middle Aged; D000068557:Olmesartan Medoxomil; D012867:Skin / Q000098:blood supply / Q000503:physiopathology; D013777:Tetrazoles / Q000008:administration & dosage*
chemical_list: D058671:Adrenergic beta-1 Receptor Antagonists; D047228:Angiotensin II Type 1 Receptor Blockers; D007093:Imidazoles; D013777:Tetrazoles; D000068557:Olmesartan Medoxomil; D008790:Metoprolol
keywords: capillary rarefaction; hypertension; microvascular dysfunction; video capillaroscopy