The metabolism of cyclohexanecarboxylic acid in the isolated perfused rat liver.

1. Cyclohexanecarboxylic acid in isolated perfused rat livers was eliminated from the perfusion system by a first-order process. 2. After 6 h, 16% was excreted in bile as cyclohexylcarbonyl beta-D-glucuronide. The remainder was present in the perfusate as unchanged cyclohexanecarboxylic acid (10%), hippuric acid (50%), hexahydrohippuric acid (2%), 3,4,5,6-tetrahydrohippuric acid (2%), cyclohexylcarbonyl-beta-D-glucuronide (2-4%) and benzoic acid (1-2%). Six per cent of the dose was associated with the red blood cell present in the perfusion medium. 3. Unlike the whole animal, the isolated rat liver produced no detectable benzoyl glucuronide. 4. The identity and kinetics of production of the metabolites are consistent with a metabolic pathway previously proposed for cyclohexanecarboxylic acid and shikimic acid.