[Relationship between gallbladder contractility and muscular fibrosis in the patients with cholecystolithiasis--immunohistochemical analysis].

The gallbladder muscular layers of the patients with cholecystolithiasis were examined to evaluate the relationship between the gallbladder contractility and fibrosis in the muscular layers. Gallbladder contractility decreased as the fibrosis of muscular layers became severe. The density of the antimacrophage (M phi) antibody positive cells in the muscular layers was apparently greater in the remarkable fibrosis group than in the unremarkable fibrosis group, and the density of the anti-TGF-beta antibody positive cells in the remarkable fibrosis group was significantly greater than in the unremarkable fibrosis group. Smooth muscle cells in the muscular layers had changed morphologically from a contractile type to a synthetic type, and fibroblasts were frequently observed in the muscular layers of the remarkable fibrosis group. Immunohistochemically, type III collagen was detected in the rough endoplasmic reticulum not only of fibroblasts but also of synthetic type-smooth muscle cells. These results suggest that the fibrosis in the muscular layers is one of the factors responsible for reduced gallbladder contractility in patients with cholecystolithiasis, and the increase of M phi, fibroblasts and synthetic type-smooth muscle cells is involved in such a fibrotic change of the gallbladder muscular layers.