title: Role of prostaglandin/cAMP pathway in the diuretic and hypotensive effects of purified fraction of Maytenus ilicifolia Mart ex Reissek (Celastraceae).
abstract: BACKGROUND
  Although Maytenus ilicifolia is used in Brazilian folk medicine as a diuretic drug, no study has been conducted to this date in order to evaluate this ethnopharmacological statement. So, the aim of this study was to evaluate possible mechanisms involved in acute diuretic activity of the ethanolic supernatant of the infusion (SEI) obtained from Maytenus ilicifolia and to assess its relationship with a hypotensive activity by a bioassay-guided fractionation using normotensive Wistar rats.
  
  
  METHODS
  The preparation obtained from the infusion (SEI) and their respective fractions (Fr·H2O and Fr·EtOAc) were orally administered in a single dose to rats. The urine excretion rate, pH, density, conductivity and content of Na(+), K(+), Cl(-) and HCO3(-) were measured in the urine of saline-loaded animals. Samples of the concentration of electrolytes, urea, creatinine, aldosterone, vasopressin and angiotensin converting enzyme (ACE) activity were evaluated in collected serum. The hypotensive activity and the involvement of nitric oxide, bradykinin and prostaglandin/cAMP pathway in the hypotensive and diuretic effects were also determined.
  
  
  RESULTS
  Water and Na(+) excretion rate were significantly increased by Fr·EtOAc and the arterial pressure was significantly reduced, while the urinary excretion of potassium and chloride were reduced. Pre-treatment with indomethacin or DDA (2',5'-dideoxyadenosine) significantly reduced the hypotensive and diuretic activity observed. All other parameters evaluated were not affected by any treatment.
  
  
  CONCLUSIONS
  The present study reveals that Fr·EtOAc obtained from Maytenus ilicifolia may present compounds responsible for diuretic and hypotensive activities, and this effect, could involve the prostaglandin/cAMP pathway.
authors.affiliation: Instituto de Ciências Biológicas, Médicas e da Saúde, Universidade Paranaense, Umuarama, PR, Brazil.
authors.forename: Thiago dos Santos Vilhena
authors.initials: Tdos S
authors.lastname: Leme
authors.forename: Thiago Bruno Lima
authors.initials: TB
authors.lastname: Prando
authors.forename: Francielly Mourão
authors.initials: FM
authors.lastname: Gasparotto
authors.forename: Priscila
authors.initials: P
authors.lastname: de Souza
authors.forename: Sandra
authors.initials: S
authors.lastname: Crestani
authors.forename: Lauro Mera
authors.initials: LM
authors.lastname: de Souza
authors.forename: Thales Ricardo
authors.initials: TR
authors.lastname: Cipriani
authors.forename: Emerson Luiz Botelho
authors.initials: EL
authors.lastname: Lourenço
authors.forename: Arquimedes
authors.initials: A
authors.lastname: Gasparotto
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D000242:Cyclic AMP / Q000378:metabolism*; D004232:Diuretics / Q000494:pharmacology*; D008297:Male; D029755:Maytenus; D010936:Plant Extracts / Q000494:pharmacology*; D011453:Prostaglandins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction
chemical_list: D000959:Antihypertensive Agents; D004232:Diuretics; D010936:Plant Extracts; D011453:Prostaglandins; D000242:Cyclic AMP
keywords: Celastraceae; Diuretic; Hypotensive; Maytenus ilicifolia; Prostaglandin