title: [HPLC-ESI/MS analysis of stachydrine and its metabolites in rat urine].
abstract: OBJECTIVE
  To identify the main metabolites of stachydrine in rat.
  
  
  METHODS
  The ionization, cleavage and chromatographic characteristics of stachydrine were studied by using high-performance liquid chromatography-electrospray ionization ion trap tandem mass spectrometry (HPLC-ESI/MS) for the first time. These characteristics of stachydrine were used as the basis for the analyses of metabolites in rat urine. The 0 - 24 h urine samples of rats after ig 25 mg x kg(-1) stachydrine were collected and purified by using C10 solid-phase extraction cartridge, and then analyzed by HPLC-ESI/MS to identify stachydrine and its metabolites.
  
  
  RESULTS
  The parent drug (stachydrine), 6 phase I metabolites (N-demethyl, dehydrogenation, ring-oxidation) and 2 phase II metabolites (glycine conjugates of 2 ring-oxidation products) were identified existing in rat urine.
  
  
  CONCLUSIONS
  The presented method was proved to be sensitive, rapid, high selective and specific for the identification of stachydrine and its metabolites in rat urine.
authors.affiliation: Hubei Province Key Lab of Bio-Technology of Traditional Chinese Medicine, Hubei University, Wuhan 430062, China.
authors.forename: Huai-Xia
authors.initials: HX
authors.lastname: Chen
authors.forename: Shao-Lin
authors.initials: SL
authors.lastname: Shen
authors.forename: Feng-Mei
authors.initials: FM
authors.lastname: Han
authors.forename: Yong
authors.initials: Y
authors.lastname: Chen
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D011392:Proline / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000378:metabolism / Q000652:urine; D051381:Rats; D017208:Rats, Wistar; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D031366:Stachys / Q000737:chemistry
chemical_list: D011392:Proline; C003342:stachydrine