Ethereal and acyl glucuronide formation in the homozygous Gunn rat

Abstract

Phenoldibromphthalein and diphenylacetic acid were administered to Wistar and to homozygous Gunn rats. Phenoldibromphthalein was found to be excreted in bile as ethereal mono- and diglucuronides and diphenylacetic acid as an acyl glucuronide. The rates of excretion of these glucuronides in the bile of both groups of animals were similar. The rates of excretion of phenoldibromphthalein and diphenylacetyl glucuronides in Gunn rat bile were much greater than the estimated maximal rate of bilirubin conjugation. It is concluded that the differences between strains of rats in bilirubin and nonbilirubin glucuronide conjugation are attributable to differences in the enzymes catalyzing their formation.