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一种已存在的大肠动物致癌物具有结肠癌促进剂的作用。为探讨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。当患者食用低脂饮食时，总胆汁酸排泄减少。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。用气相色谱对结果进行了分析。在此期间，尝试用高压液相色谱(HPLC)分析粪便胆汁酸。样品进样用岛津仪器(RF-530)，色谱柱为Zorbax C8。分别测定胆汁酸、鹅去氧胆酸、脱氧胆酸和胆石酸。但用高效液相色谱法无法分析出胆汁酸。在本实验中，用气相色谱分析粪便胆汁酸的效果似乎要好于用高效液相色谱法。

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.