The metabolism of cyclohexanecarboxylate in the rat.

In the rat, cyclohexanecarboxylate was metabolized and excreted (mostly in the urine) as hippurate, hexahydrohippurate, 3,4,5,6-tetrahydrohippurate and benzoyl and cyclohexylcarbonyl beta-glucuronides. The pattern of metabolism is dose-dependent. With decreasing dose a progressive increase in the conversion into hippurate occurred. This was largely at the expense of glucuronide formation, although the proportions of hexahydro- and tetrahydro-hippurate were also decreased. The observed formation of hexahydrohippurate and 3,4,5,5-tetrahydrohippurate substantiates the proposed mechanism of aromatization of cyclohexanecarboxylate. It appears that these compounds arise via glycine conjugation of active intermediates in the aromatization process. Hexahydrohippurate and 3,4,5,6-tetrahydrohippurate may occur in the urine of rats as new mitabolities of shikimate, dependent for their formation on microbial metabolism.