Noshiro H, Hotokezaka M, Higashijima H, Iwamoto T, Nakahara S, Mibu R, Soloway R D, Chijiiwa K
Department of Surgery I, Kyushu University, Faculty of Medicine, Fukuoka, Japan.
Dig Dis Sci. 1996 Dec;41(12):2423-32. doi: 10.1007/BF02100138.
A high prevalence of gallstones has been described in patients following colectomy. The aim of this study was to examine whether lithogenicity is attributed to colectomy. In the present study, changes in gallbladder bile composition and the mechanism of gallstone formation after colectomy were examined in dogs. Ten mongrel dogs underwent restorative proctocolectomy. Seven dogs which received sham operations served as controls. Over a 12-week postoperative period, samples of gallbladder bile, formed gallstones and serum were collected and analyzed. In 7 of the 10 (70%) colectomized dogs, gallstones were found in the gallbladder, while the control dogs had no stones. Macroscopically the gallstones were similar to black pigment stones observed in humans. Chemical analysis and Fourier transform-infrared spectroscopy examination revealed that the stones were composed mainly of sodium bilirubinate and proteins, with minor amounts of calcium salts and cholesterol. Significant increases in biliary pH and concentrations of ionized calcium and unconjugated bilirubin were observed in the gallbladder bile of the colectomy group compared with that of the control group. The total bile acid and total bilirubin concentrations were significantly decreased in the colectomy group. Cholesterol crystal nucleation did not occur. The inhibitory effect of gallbladder bile on calcium carbonate precipitation in an in vitro assay system was preserved even after colectomy. In conclusion, proctocolectomy increases the concentration of unconjugated bilirubin in gallbladder bile and induces pigment gallstones which are composed mainly of sodium bilirubinate and proteins since calcium ions and cholesterol are stabilized in dogs.
结肠切除术后患者的胆结石患病率较高。本研究的目的是检验结石形成是否归因于结肠切除术。在本研究中，对狗结肠切除术后胆囊胆汁成分的变化及胆结石形成机制进行了研究。10只杂种狗接受了保留直肠的结肠切除术。7只接受假手术的狗作为对照。在术后12周内，收集并分析胆囊胆汁、形成的胆结石和血清样本。10只接受结肠切除术的狗中有7只（70%）在胆囊中发现了胆结石，而对照狗没有结石。从宏观上看，这些胆结石与在人类中观察到的黑色色素结石相似。化学分析和傅里叶变换红外光谱检查显示，结石主要由胆红素钠和蛋白质组成，还有少量钙盐和胆固醇。与对照组相比，结肠切除组胆囊胆汁中的胆汁pH值、离子钙和未结合胆红素浓度显著升高。结肠切除组的总胆汁酸和总胆红素浓度显著降低。未发生胆固醇晶体成核现象。即使在结肠切除术后，胆囊胆汁在体外测定系统中对碳酸钙沉淀的抑制作用仍然存在。总之，由于狗体内钙离子和胆固醇处于稳定状态，保留直肠的结肠切除术会增加胆囊胆汁中未结合胆红素的浓度，并诱发主要由胆红素钠和蛋白质组成的色素性胆结石。
