Effect of the lithogenic diet on gallbladder histology in wild-type and PSTI-I tg mice. (A) Gallbladder histology was normal in both wild-type and PSTI-I tg mice on the normal diet. The lithogenic diet caused histopathological changes of inflammation, thickened muscular wall, increased numbers of neutrophils in the epithelium and lamina propria, reactive epithelial changes, and altered papillary mucosal architecture. (B) Semiquantitative histological score (N = 5). Wild-type, open bars; PSTI-I tg, filled bars; (**P < 0.01; ***P < 0.001)