title: Hancornia speciosa Gomes induces hypotensive effect through inhibition of ACE and increase on NO.
abstract: BACKGROUND
  The leaves of Hancornia speciosa Gomes are popularly used in Brazil to treat diabetes and hypertension. Cardiovascular diseases are the main cause of death worldwide and their incidences are increasing in Brazilian population. The present study aimed to investigate the hypotensive effect and the mechanism of action of Hancornia speciosa Gomes.
  
  
  METHODS
  A fraction of the ethanolic extract of leaves from Hancornia speciosa (SFH) was obtained and standardized by its content on rutin, bornesitol and quinic acid. Systolic blood pressure (SBP) of normotensive mice was measured by tail plethysmography. SFH was given orally and SBP was monitored for 5h. Angiotensin-converting enzyme (ACE) inhibitor activity of SFH (1mg/kg) or captopril (10mg/kg) was measured by colorimetric methods. Serum nitrite levels were measured by spectrophotometry.
  
  
  RESULTS
  SFH induced a dose-dependent hypotensive effect in normotensive mice. The serum activity of ACE and the level of angiotensin II were significantly reduced by SFH and by captopril. Administration of SFH induced a significant increase on plasmatic level of nitrites and the systemic inhibition of nitric oxide synthase by L-NAME (20mg/kg) reduced the hypotensive effect of SFH.
  
  
  CONCLUSIONS
  The present work demonstrated that Hancornia speciosa has a potent hypotensive effect in normotensive mice. The inhibition of ACE leading to reduction on angiotensin II and increase on NO levels might account for the hypotensive effect. These results support the use of Hancornia speciosa by traditional medicine as antihypertensive.
authors.affiliation: Department of Pharmacology, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, Brazil.
authors.forename: G C
authors.initials: GC
authors.lastname: Silva
authors.forename: F C
authors.initials: FC
authors.lastname: Braga
authors.forename: M P
authors.initials: MP
authors.lastname: Lima
authors.forename: J L
authors.initials: JL
authors.lastname: Pesquero
authors.forename: V S
authors.initials: VS
authors.lastname: Lemos
authors.forename: S F
authors.initials: SF
authors.lastname: Cortes
mesh_terms: D000284:Administration, Oral; D000804:Angiotensin II / Q000097:blood; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D029062:Apocynaceae / Q000737:chemistry; D001794:Blood Pressure / Q000187:drug effects*; D002216:Captopril / Q000494:pharmacology; D000431:Ethanol / Q000737:chemistry; D008297:Male; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000378:metabolism; D009573:Nitrites / Q000097:blood; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves; D010946:Plants, Medicinal; D010991:Plethysmography; D012997:Solvents / Q000737:chemistry; D013997:Time Factors; D015854:Up-Regulation
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D009573:Nitrites; D010936:Plant Extracts; D012997:Solvents; D000804:Angiotensin II; D009569:Nitric Oxide; D000431:Ethanol; D002216:Captopril; D019001:Nitric Oxide Synthase