Takahashi M, Maeda Y, Tashiro H, Eto T, Goto T, Sanada O
Department of Surgery, Chugoku Rosai Hospital, Hiroshima, Japan.
World J Surg. 1990 Sep-Oct;14(5):628-34; discussion 635. doi: 10.1007/BF01658810.
We investigated a newly synthesized conjugate of ursodeoxycholic acid with para-aminobenzoic acid (PABA) to determine its suitability to evaluate enteric bacteria. This compound, PABA-UDCA, is deconjugated by cholylglycine hydrolase to release free PABA whereas it is completely resistant to deconjugation by pancreatic and intestinal mucosal enzymes. In bacteriological experiments, almost all of the microorganisms which split glycocholic acid deconjugated this compound. In animal experiments, urinary excretions of PABA were measured for 6 hours following oral administration of 10 mg PABA-UDCA. Ten control rats excreted 338.5 +/- 43.8 micrograms (mean +/- SD) of PABA; 10 rats with intestinal bacterial overgrowth due to enteric stagnant loops excreted more (673.6 +/- 222.1 micrograms; p less than 0.01), whereas 10 rats in each of 8 groups with intestinal antisepsis by oral administration of various antibiotics excreted significantly less (p less than 0.001) (ampicillin + doxycycline + fradiomycin: 18.3 +/- 16.7, polymixin B + tinidazole: 14.0 +/- 8.0, polymixin B: 224.9 +/- 74.3, tinidazole: 42.7 +/- 27.3, kanamycin: 50.3 +/- 18.2, clindamycin: 57.4 +/- 23.3, vancomycin: 70.4 +/- 27.0, and paromomycin: 160.4 +/- 51.9 micrograms). These observations indicate that this compound is likely to offer a simple and rapid method for evaluation of intestinal microorganisms without the use of radioisotopes or expensive, special apparatus.
我们研究了一种新合成的熊去氧胆酸与对氨基苯甲酸（PABA）的共轭物，以确定其评估肠道细菌的适用性。这种化合物，即PABA-UDCA，可被胆酰甘氨酸水解酶去共轭以释放游离的PABA，而它对胰腺和肠黏膜酶的去共轭作用完全具有抗性。在细菌学实验中，几乎所有能分解甘氨胆酸的微生物都能使该化合物去共轭。在动物实验中，口服10 mg PABA-UDCA后6小时测量PABA的尿排泄量。10只对照大鼠排泄了338.5±43.8微克（平均值±标准差）的PABA；10只因肠道淤滞环导致肠道细菌过度生长的大鼠排泄量更多（673.6±222.1微克；p<0.01），而8组通过口服各种抗生素进行肠道抗菌处理的每组10只大鼠排泄量显著减少（p<0.001）（氨苄西林+强力霉素+弗氏霉素：18.3±16.7，多粘菌素B+替硝唑：14.0±8.0，多粘菌素B：224.9±74.3，替硝唑：42.7±27.3，卡那霉素：50.3±18.2，克林霉素：57.4±23.3，万古霉素：70.4±27.0，以及巴龙霉素：160.4±51.9微克）。这些观察结果表明，该化合物可能提供一种无需使用放射性同位素或昂贵特殊设备的简单快速的肠道微生物评估方法。
