title: Can pigment gallstones be induced by biliary stricture and prevented by medicine in Guinea pigs?
abstract: OBJECTIVE
  To determine the relationship between biliary stricture and pigment gallstone formation, and the prevention of pigment gallstones with medicine.
  
  
  METHODS
  One hundred and eighteen male guinea pigs were randomly divided into four groups: stricture group (S, n = 30) underwent partial ligation of common bile duct, and fed on regular chow; S plus medicine group (S+M, n = 27) underwent the same operation but fed on medicinal chow (0.3 g chenodeoxycholic acid, 0.5 g glucurolactone, and 0.5 g aspirin were mixed up in 1.2 kg regular chow); medicinal control group (C+M, n = 30) was free of operation, and fed on medicinal chow; and control group (C, n = 31) was free of operation and fed on regular chow. One week later, laparotomy was performed, and the bile of gallbladder was collected, measured, and cultured.
  
  
  RESULTS
  Gallstones were identified. Pigment gallstones were induced by biliary stricture in 95% (22/23) of S group. In the S+M group, the incidence of gallstone was reduced to 55% (11/20, vs S group, P < 0.01). The changes of indirect bilirubin and ionized calcium in the bile were consistent with gallstone incidences.
  
  
  CONCLUSIONS
  Biliary stricture can cause pigment gallstone formation in guinea pigs, and the medicines used can lower the incidence of gallstones. The bilirubin and ionized calcium play important roles in pigment gallstone formation.
authors.affiliation: Department of Surgery, Third Hospital of Peking University, 49 North Garden Road, Haidian District, Beijing 100083, China. xuzhi123456@sohu.com
authors.forename: Zhi
authors.initials: Z
authors.lastname: Xu
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Ling
authors.forename: Wan-Hua
authors.initials: WH
authors.lastname: Zhang
authors.forename: Xiao-Si
authors.initials: XS
authors.lastname: Zhou
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use*; D001241:Aspirin / Q000627:therapeutic use*; D001663:Bilirubin / Q000502:physiology; D002118:Calcium / Q000502:physiology; D002635:Chenodeoxycholic Acid / Q000627:therapeutic use*; D003135:Common Bile Duct / Q000503:physiopathology*; D003251:Constriction, Pathologic / Q000150:complications / Q000503:physiopathology; D004359:Drug Therapy, Combination; D042882:Gallstones / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control*; D005765:Gastrointestinal Agents / Q000627:therapeutic use*; D006168:Guinea Pigs; D008026:Ligation / Q000009:adverse effects; D008297:Male; D010858:Pigmentation; D011897:Random Allocation; D015996:Survival Rate
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D005765:Gastrointestinal Agents; D002635:Chenodeoxycholic Acid; D001241:Aspirin; D001663:Bilirubin; D002118:Calcium