Relation between renal and hepatic excretion of drugs: X. Excretion of nalorphine in young and adult rats pretreated with hormones or xenobiotics.
Different processes are involved in renal and hepatic excretion of organic anions and cations. In contrast to our knowledge of anion excretion, information about cation transport in kidney and liver is relatively scarce. In this study, the elimination of nalorphine was investigated to characterize the relation between renal and hepatic excretion of organic cations. Nalorphine is excreted effectively both via kidney and liver. However, its hepatic excretion dominates in adult rats. In young, 20-day-old animals biliary nalorphine elimination is immature and the excreted amounts are significantly lower. Renal excretion of nalorphine is quite similar in rats of both ages. After bile duct ligation renal excretion of nalorphine increases significantly in adult rats whereas it remains unchanged in young ones. Remarkably, after bilateral nephrectomy hepatic elimination of nalorphine is even diminished in both age groups. In further experiments renal excretion of nalorphine could be stimulated in adult rats after repeated administration of trometamol, triiodothyronine, or dexamethasone; these treatments had no consequences on biliary secretion of nalorphine.
Fleck
C
C
Institute of Pharmacology and Toxicology, Friedrich Schiller University, Jena.
Schultz
M
M
Seidel
D
D
Bräunlich
H
H
D000375:Aging; D000818:Animals; D001646:Bile / Q000378:metabolism*; D003518:Cyclopenthiazide / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D005260:Female; D007668:Kidney / Q000378:metabolism*; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D009269:Nalorphine / Q000493:pharmacokinetics* / Q000652:urine; D009392:Nephrectomy; D051381:Rats; D011919:Rats, Inbred Strains; D014284:Triiodothyronine / Q000494:pharmacology; D014325:Tromethamine / Q000494:pharmacology
D014325:Tromethamine; D014284:Triiodothyronine; D003907:Dexamethasone; D009269:Nalorphine; D003518:Cyclopenthiazide