title: Dose dependence effects of ionizing radiation on bile acid metabolism in the rat.
abstract: OBJECTIVE
  To study radiation dose-related changes of individual or total bile acids in various physiological fluids in order to identify potential bio-indicators of radiation-induced gastrointestinal injuries.
  
  
  METHODS
  Wistar rats were sham- or whole-body gamma irradiated (1-12Gy). Total and individual bile acids were quantified, 3 days after exposure, in bile collected after catheterization of the bile duct. Total bile acid concentrations were also measured in plasma and colonic contents 1, 2 and 3 days after irradiation. These concentrations were determined by an enzymatic method whereas individual bile acids were quantified by HPLC.
  
  
  RESULTS
  In bile, whereas total bile acid concentration remained unchanged after irradiation whatever the dose, the proportion of dihydroxy bile acids in the pool of total bile acids was gradually increased with the irradiation dose, especially from 8 Gy. In plasma samples, total bile acid concentrations fell for doses higher than 10 Gy. In colonic contents, bile acid concentrations increased progressively with time (from 1 to 3 days) and with irradiation dose (from 1 to 12Gy), reaching a plateau 3 days after exposure for doses higher than 10 Gy.
  
  
  CONCLUSIONS
  These results show that changes in colonic bile acid concentrations which are reflected in faeces are perhaps a useful parameter to improve diagnosis and prognosis of radiation-induced gastrointestinal damage since it probably reflects directly intestinal bile acid malabsorption.
authors.affiliation: Institut de Protection et de Sûreté Nucléaire, Dértement de Protection de la santé de l'Homme et de Dosimétrie, Laboratoire de Radiobiologie Digestive, IPSN, B.P. no. 6, F 92265 Fontenay-aux-Roses Cedex, France. pascale.scanff@ipsn.fr
authors.forename: Pascale
authors.initials: P
authors.lastname: Scanff
authors.forename: S
authors.initials: S
authors.lastname: Grison
authors.forename: T
authors.initials: T
authors.lastname: Marais
authors.forename: P
authors.initials: P
authors.lastname: Gourmelon
authors.forename: N M
authors.initials: NM
authors.lastname: Griffiths
mesh_terms: D000818:Animals; D001647:Bile Acids and Salts / Q000097:blood / Q000378:metabolism*; D001652:Bile Ducts / Q000528:radiation effects*; D002851:Chromatography, High Pressure Liquid; D004307:Dose-Response Relationship, Radiation; D008297:Male; D011839:Radiation, Ionizing; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D001647:Bile Acids and Salts