Correlation between fecal bile acid and diet in carcinogenesis of the colon.

动物模型实验表明，脱氧胆酸和石胆酸对大肠动物致癌物具有结肠肿瘤促进作用。研究了结肠癌患者胆汁酸排泄与饮食的关系。结肠癌患者总胆汁酸排泄量高于消化性溃疡和结肠息肉患者。在结肠癌患者中，入院后胆酸和鹅去氧胆酸的排泄量在医院饮食中减少。当患者采用低脂饮食时，总胆汁酸排泄量减少。研究发现，医院饮食改变了结肠癌患者粪便胆汁酸的组成和数量。结果用气相色谱法进行了分析。本文采用高压液相色谱法对粪胆汁酸进行了分析。样品采用Shimazu仪器（RF-530）， Zorbax C8柱进样。分别对胆酸、鹅去氧胆酸、去氧胆酸和石胆酸进行分析。而胆汁酸不能用高效液相色谱法分析。在本实验中，气相色谱法比高效液相色谱法分析粪胆汁酸的效果更好。

Animal model experiments indicate that deoxycholic acid and lithocholic acid act as colon tumor promoters to an extablished large bowel animal carcinogen. The correlation between becal bile acid excretion and diet was studied in patients with colon cancer. Total bile acid excretion in patients with colon cancer were higher than taht in patients with peptic ulcer and colon polyp. In patients with colon cancer, cholic acid and chenodeoxycholic acid excretion after admission were decreased on the hospital diet. When patients were on low fat diet, total bile acid excretion was decreased. It was found that the hospital diet altered the composition and amount of fecal bile acids in patients with colon cancer. These results were analized by gas chromatography. In this time, fecal bile acids were tried to analize by high pressure liquid chromatography ( HPLC) . Samples were injected for HPLC using Shimazu instrument (RF-530) with Zorbax C8 column. Individual bile acid was analyzed for cholic acid, chenodeoxycholic acid, deoxycholic acid and lithocholic acid. But bile acide could not be analyzed by HPLC. It should seem that analysis of fecal bile acid by gas chromatography is better than that by HPLC in this experiment.