[In vitro nucleation factors--mucus glycoprotein and proteins: changes and mechanisms in the process of sludge and gallstone formation].

Both mucus glycoprotein (MGP) and proteins are in vitro nucleation factors. Biliary sludge proved to be a precursor of gallstones. In this study, the MGP in gallbladder bile (GB) and the RNA content of the membrane-bound polyribosome in gallbladder epithelium were significantly higher in the sludge group than that in gallstone and control group. These facts demonstrated the increased synthesis and secretion of glycoproteins in the prestone stage. The RNA content of free polyribosome in the sludge group was also significantly greater than that in the control group so that in prestone stage there was an increase of cell proliferation in the gallbladder epithelium. Patients with sludge and cholesterol gallstones had significantly higher protein concentrations in GB than those without gallstones or with pigment stones. The gallbladder-hepatic bile ratio of proteins was significantly less than that of cholesterol, and there was a highly positive correlation between glycoproteins and proteins in GB. Therefore, the only reasonable explanation for the higher protein content in these two kinds of patients was that the mucus selectively inhibited protein absorption in the gallbladder. The increases in MGP and protein content in GB during the embryonic stage of gallstones might play a significant role in the formation of both cholesterol and pigment gallstones.