TY - JOUR T1 - Differences in urinary metabolic profile from di-n-butyl phthalate-treated rats and hamsters. A possible explanation for species differences in susceptibility to testicular atrophy. JF - Drug Metabolism and Disposition JO - Drug Metab Dispos SP - 59 LP - 61 VL - 11 IS - 1 AU - P M Foster AU - M W Cook AU - L V Thomas AU - D G Walters AU - S D Gangolli Y1 - 1983/01/01 UR - http://dmd.aspetjournals.org/content/11/1/59.abstract N2 - A high-performance liquid chromatographic method for the direct analysis of the urinary metabolites of di-n-butyl phthalate (DBP) is described. In both rats and hamsters the major urinary metabolite found after treatment with either DBP or mono-n-butyl phthalate (MBP) was MBP glucuronide and not MBP as previously reported. The levels of unconjugated MBP in the urine of animals treated with DBP or MBP were three- to fourfold higher in the rat than in the hamster. However, intestinal esterase activities were comparable in the two species, whereas the activities of testicular beta-glucuronidase were significantly higher in rats compared to hamsters. It is possible that the differences in the concentration of free MBP, a substance known to produce testicular damage directly in the rat in vitro, may account for the lack of injury seen in hamsters after oral treatment with either DBP or MBP. ER -