title: Hepatic handling of a gamma-emitting bile salt derivative, 123I-cholylglycylhistamine, in the dog.
abstract: The hepatic handling of the bile salt derivative 123I-cholylglycylhistamine has been compared with that of the physiologic bile salt taurocholate in boxer dogs equipped with a Thomas duodenal cannula. After intravenous injection of trace amounts, 123I-cholylglycylhistamine and 14C-taurocholate disappeared from plasma with nearly identical disappearance rate constants. Excellent scintiscans of the liver were obtained with the Anger camera after injection of 3 mCi of 123I-cholylglycylhistamine. Monitoring of radioactivity over a hepatic region of interest revealed rapid uptake of 123I-cholylglycylhistamine by the liver, which reached a maximum 5.7 +/- 0.4 min after injection. The biliary excretion rates of the compounds closely paralleled each other, reaching their maximum within 15 min after injection. Cumulative biliary excretion within 45 min was 58.5 +/- 2.9% and 61.4 +/- 5.0% of the dose for 123I-cholylglycylhistamine and 14C-taurocholate, respectively. Modification of the side chain and gamma-labelling of bile salts may provide scintigraphic agents for the study of the biliary system, which in the behaviour closely resemble the physiologic parent compounds.
mesh_terms: D000818:Animals; D001646:Bile / Q000032:analysis; D004285:Dogs; D006000:Glycocholic Acid / Q000031:analogs & derivatives* / Q000032:analysis / Q000138:chemical synthesis / Q000378:metabolism; D006632:Histamine / Q000031:analogs & derivatives* / Q000032:analysis / Q000138:chemical synthesis / Q000378:metabolism; D007457:Iodine Radioisotopes; D008099:Liver / Q000000981:diagnostic imaging / Q000378:metabolism*; D011877:Radionuclide Imaging; D013656:Taurocholic Acid / Q000378:metabolism*
chemical_list: D007457:Iodine Radioisotopes; D013656:Taurocholic Acid; C023966:cholylglycylhistamine; D006632:Histamine; D006000:Glycocholic Acid