title: Antinociceptive activity and chemical composition of Wei-Chang-An-Wan extracts.
abstract: BACKGROUND
  Currently, famous traditional Chinese medicine formulas have undergone re-evaluation and development in China. Wei-Chang-An-Wan (WCAW) as one of them has been used for treating various gastrointestinal diseases for several decades. The secondary development of WCAW is in progress so as to interpret the effective material basis or find new pharmacological activity.
  
  
  OBJECTIVE
  To evaluate the antinociceptive effect of methanol extract of WCAW (ME) as well as four fractions (P.E., EtOAc, n-BuOH, H2O) and obtain information on the correlation between the contents of the fractions and antinociceptive effect.
  
  
  METHODS
  ME was divided into four parts extracted by petroleum ether, ethyl acetate and n-butanol. Antinociceptive activity was evaluated by three models of acetic acid-induced writhing, formalin and hot-plate test in mice after repetitive administration of ME at 200, 400 or 800 mg/kg, P.E. 132 mg/kg, EtOAc 106 mg/kg, n-BuOH 176 mg/kg and H2O 176 mg/kg for six days. The chemical compounds were analyzed by HPLC-ESI-MS.
  
  
  RESULTS
  ME at 800 mg/kg inhibited acid-induced writhing by 84.69%, and reduced the licking time of second phase in formalin test by 53.23%. The inhibition rates in acid-induced writhing of P.E., EtOAc, n-BuOH and H2O were 27.79, 33.85, 38.97 and 37.69%, respectively, and in formalin test about 50%. They had no effect on the hot-plate test. HPLC-ESI-MS analysis showed that 68 chemical compounds were detected and 41 compounds were identified from ME.
  
  
  CONCLUSIONS
  The results obtained herein indicate that WCAW possesses the antinociceptive activity that provides a new aspect in clinical application.
authors.affiliation: Tianjin Key Laboratory for Modern Drug Delivery & High-Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Liu
authors.forename: Jingze
authors.initials: J
authors.lastname: Zhang
authors.forename: Wenyuan
authors.initials: W
authors.lastname: Gao
authors.forename: Changxiao
authors.initials: C
authors.lastname: Liu
mesh_terms: D000700:Analgesics / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D005260:Female; D008297:Male; D008516:Medicine, Chinese Traditional; D051379:Mice; D010146:Pain / Q000188:drug therapy* / Q000473:pathology; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D012997:Solvents / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods
chemical_list: D000700:Analgesics; D004365:Drugs, Chinese Herbal; D010936:Plant Extracts; D012997:Solvents; C545640:Wei-Chang-An-Wan