Metabolism in vivo of all-trans-[11-3H]retinoic acid after an oral dose in rats. Characterization of retinoyl beta-glucuronide in the blood and other tissues.
Soon after [11-3H]retinoic acid (RA) (1.1 x 10(8) d.p.m.) was administered orally to rats either as a large dose (115 micrograms = 0.38 mumol/rat) or mixed with unlabelled RA as a huge dose (22 mg = 73.33 mumol/rat), retinoyl beta-glucuronide (RAG) was identified and characterized as a significant metabolite in the serum and small intestine. Of the administered dose, 70% remained unchanged as retinoic acid in the stomach up to 1 h. Significant amounts of 5,6-epoxyretinoic acid, 4-hydroxyretinoic acid, esters of retinoic acid and several polar retinoids, including 4-oxoretinoic acid, were also detected in the stomach. No significant difference was observed in the nature of the retinoids found after a large or a huge dose; however, the ratio of RAG/RA was higher after a huge dose than after a large dose. Thus RAG, which is biologically active in vivo and in vitro, is formed quickly in significant amounts in tissues after a dose of RA.
Barua
A B
AB
Department of Biochemistry and Biophysics, Iowa State University, Ames 50011.
Gunning
D B
DB
Olson
J A
JA
D000284:Administration, Oral; D000818:Animals; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid; D005260:Female; D008297:Male; D011247:Pregnancy; D011865:Radioisotope Dilution Technique; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors; D014018:Tissue Distribution; D014212:Tretinoin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000032:analysis / Q000097:blood / Q000378:metabolism* / Q000493:pharmacokinetics; D014316:Tritium
D014316:Tritium; C026787:retinoyl glucuronide; D014212:Tretinoin