Englert E, Harman C G, Freston J W, Straight R C, Wales E E
Am J Dig Dis. 1977 Apr;22(4):305-14. doi: 10.1007/BF01072187.
Experimental diet-induced dog gallstones contained mainly protein, mucous substances, bile salts, bilirubin, an insoluble pigment which formed an insoluble black residue after acid hydrolysis, and only traces of cholesterol. Added dietary cholesterol was necessary to pigmented gallstone production and led to hypercholesterolemia. In bile, the ratio of cholesterol to bile salts was increased, but phospholipids were increased and cholesterol insolubility was not found. Dry weight, osmolality, and concentration of sodium and potassium in bile were reduced, but were not considered sufficient to influence micelle formation or lipid-pigment solubility. Taurine was reduced in serum and bile and unconjugated bile acids appeared in gallbladder bile; the pKa of these acids is near the pH of bile in these animals and may have caused precipitation of bile acids, accounting for their presence in the stones. Bile cultures were sterile. Total bilirubin content was unaltered but the methods used did not exclude the presence of unconjugated bilirubin as a potential cause of pigment precipitation in aqueous bile. Increased numbers of secretory vesicles occurred in gallbladder epithelium and large amounts of mucus were in the epithelial crypts. These observations suggest that bile proteins or mucous substances are important to lithogenesis in this model.
实验性饮食诱导的犬胆结石主要含有蛋白质、黏液物质、胆汁盐、胆红素、一种不溶性色素，该色素在酸水解后形成不溶性黑色残渣，仅含微量胆固醇。添加饮食胆固醇对色素性胆结石的形成是必要的，并导致高胆固醇血症。在胆汁中，胆固醇与胆汁盐的比例增加，但磷脂增加且未发现胆固醇不溶性。胆汁的干重、渗透压以及钠和钾的浓度降低，但认为不足以影响微胶粒形成或脂质色素溶解性。血清和胆汁中的牛磺酸减少，胆囊胆汁中出现未结合胆汁酸；这些酸的pKa接近这些动物胆汁的pH值，可能导致胆汁酸沉淀，这解释了它们在结石中的存在。胆汁培养无菌。总胆红素含量未改变，但所用方法并未排除未结合胆红素作为水性胆汁中色素沉淀潜在原因的存在。胆囊上皮中分泌小泡数量增加，上皮隐窝中有大量黏液。这些观察结果表明，胆汁蛋白或黏液物质在该模型的结石形成中很重要。
