Basic Studies on 5-(7-Hydroxy-3-0-phosphonochoIyI)aminosalicylic Acid for the Evaluation of Microbial Overgrowth

摘要

A newly synthesized conjugate of 7-hydroxy-3-0-phosphonocholic acid (ursodeoxycholic acid monophosphate) with 5-aminosalicylic acid (5-ASA-UDCA monophosphate) was investigated to determine its suitability for the evaluation of enteric bacteria. This compound, 5-ASA-UDCA monophosphate, was efficiently deconjugated by cholylglycine hydrolase to release 5-ASA, whereas it was completely resistant to deconjugation by pancreatic and intestinal mucosal enzymes. In everted gut sac experiments, 5-ASA-UDCA monophosphate was not actively absorbed from any part of the small intestine. In animal experiments, urinary excretions of /V-acetyl-5-ASA (Ac-5ASA) were measured for 24 h following the oral administration of 20 mg of 5-ASA-UDCA monophosphate. Control rats excreted 276.3 + 89.0 fig (mean + S.E.) of Ac-5ASA, whereas the rats with intestinal bacterial overgrowth excreted more (1224.1 ±231.5/ig; /><0.01). These basic studies indicate that this compound is likely to offer a simple method for the evaluation of microbial overgrowth without the use of radioisotopes or expensive, special apparatus.