A MICROCHOLANGIOGRAPHIC STUDY OF LIVER-DISEASE MODELS IN RATS

Rationale and Objectives. Rats develop hepatobiliary injury due to sma ll bowel bacterial overgrowth (SBBO) that, at specimen, resembles chol angiography sclerosing cholangitis. To better visualize the smaller bi le ducts, we used microcholangiography to determine the spectrum of bi liary lesions in this and five ether models of liver disease, Methods. The models studied were as follows: (1) Surgically created jejunal, s elf-filling blind loops induce SBBO. (2) Intraperitoneal injection of a bacterial cell wall polymer, peptidoglycan-polysaccharide (PG-PS), c auses granulomatous hepatitis. (3) Intraperitoneal injection of endoto xin (lipopolysaccharide) causes sinusoidal congestion and shock. (4) B ile duct ligation induces bile duct proliferation. (5) Alpha-naphthyl- isothiocyanate (ANIT) induces bile duct proliferation, (6) Carbon tetr achloride (CCl4) causes fibrosis and cirrhosis. Warmed barium sulfate, gelatin, and saline were injected in the extrahepatic bile duct. Live r slices (2 mm) underwent microradiographic techniques, and images wer e correlated with histology. Results. Rats with SBBO had irregular and dilated extrahepatic bile ducts with thickened walls. Rats treated wi th endotoxin and CCl4 had normal microcholangiograms. Bile duct prolif eration was identified following ANIT and bile duct ligation. Rats giv en PG-PS demonstrated irregular intrahepatic bile ducts. Microcholangi ograms following SBBO and PG-PS showed similarities including focal du ctal dilatation, narrowing, proliferation, and destruction. Conclusion . Various models of liver injury induce characteristic cholangiographi c appearances. Microcholangiography is useful in examining biliary tra ct lesions and complements histology.