无菌豚鼠形成胆色素结石的动物模型

The Germ-free Guinea-pig as an Animal Model of Pigment Gallstone

无菌豚鼠胆囊结石诱发率很高。胆囊结石和胆囊胆汁成份分析表明,无菌豚鼠胆囊内产生的结石为色素型结石,其胆汁特征与人色素型结石类同,提示无菌豚鼠可作为研究胆色素类结石的实验动物模型。

In the gallbladders of germ-free guinea-pigs, biliary sludge appeared in all 4 two-week-old animals and concrete gallstones appeared at the age of four weeks in all of 9 animals. Qualitative analysis of the gallstones revealed positive bili-rubin reactions. Infrared spectrum indicated that the gallstones contained calcium bilirubinate, phosphate and protein. These characteristics are similar to those of gallstones induced in guinea-pigs by partial ligation of the common bile duct without infection. There was no stone in the control group. At the age of four weeks, the indirect reactive bilirubin (IB, represent UCB) concentration in gallbladder bile from germ-free guinea-pigs (0.84±0.16mg/dl, n=8) was higher than that of control animals (0.28±0.12mg/dl, n=9,P<0.05); as was the ratio of ionized calcium to total calcium (0.28 ± 0.04, n=8, vs 0.16±0.03, n=7, P<0.05). Thus, the characteristics of gallbladder bile in germ-free guinea-pigs (which are susceptible to pigment stones) are consistent with those of bile from human beings with pigment gallstones. Since the presence of intestinal flora is essential for the normal metabolism of bile salts and the regulation of their en-terohepatic circulation, the germ-free state of the 'guinea-pigs must have been responsible for the gallstone formation in these animals.Our experiments have shown that germ-free guinea-pigs provide a useful animal model for investigating the role of intestinal flora and bile salts metabolism in pigment gallstone formation. The : gallstone incidence in this animal model is high, and the experimental period is short.