Biliary metabolites of all-trans-retinoic acid in the rat.
Biliary metabolites from physiological doses of all-trans-[10-3H]retinoic acid were examined in normal and vitamin A-deficient rats. The bile from normal and vitamin A-deficient rats contained approximately 60% of the administered dose following a 24-h collection period. However, vitamin A-deficient rats show a 6-h delay in the excretion of radioactivity compared to normal rats. Retinoyl-beta-glucuronide excretion was particularly sensitive to the vitamin A status of the rats. In normal rats, retinoyl-beta-glucuronide reached a maximum concentration of 235 pmol/ml of bile 2 h following the dose and then rapidly declined. Vitamin A-deficient rats show a relatively constant concentration of this metabolite (100-150 pmol/ml of bile) over a 10-h collection period. Retinoic acid excretion was low in both normal and deficient rats. The concentration of retinotaurine, a recently identified biliary metabolite, was approximately equal to retinoyl-beta-glucuronide in normal rats and appeared in the bile 2 h later than the glucuronide.
D000818:Animals; D001646:Bile / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D051381:Rats; D014212:Tretinoin / Q000031:analogs & derivatives / Q000378:metabolism*; D014802:Vitamin A Deficiency / Q000378:metabolism*
C026787:retinoyl glucuronide; D014212:Tretinoin; C035166:retinotaurine