Inflammatory properties of bile from dogs with pigment gallstones

BACKGROUND: Gallbladder inflammation and mucus hypersecretion are prominent features of cholesterol and pigment gallstones in humans and animals. The factors leading to inflammation and mucus hypersecretion are poorly understood. These studies examine the inflammatory potential of bile from dogs with pigment gallstones. METHODS: Dogs fed a methionine-deficient diet that produces pigment gallstones by 6 weeks were compared to normal dogs. Mucus layer thickness, myeloperoxidase activity, and interleukin-1- like activities were measured in canine gallbladder. The inflammatory potential of canine bile was determined by measuring mucus layer thickness, sodium absorption, myeloperoxidase activity and interleukin-1-like activity in guinea pig gallbladders exposed to normal and lithogenic canine bile for 4 hours. RESULTS: Mean mucus layer thickness, myeloperoxidase, and interleukin- 1 activity were significantly greater in canine gallbladders containing pigment gallstones. Bile from dogs with pigment gallstones markedly increased mucus layer thickness, myeloperoxidase activity, and interleukin-1 activity and decreased sodium absorption in normal guinea pig gallbladder. These effects were not eliminated by centrifuging bile to remove crystals and gallstones. CONCLUSIONS: Canine bile from dogs with pigment gallstones contains soluble factors capable of causing inflammation in the gallbladder wall.