Distribution and pharmacokinetics of triamterene in rats.
The tissue distribution of 14C-triamterene was examined in the fact. After intravenous administration of 14C-triamterene, high concentration ratios between tissues and blood were found in most tissues except the brain, fat, and testes. The maximal concentration of the drug was in the kidneys, liver, heart, lungs, and skeletal muscle within the first 20 min, when the maximal natriuresis was observed. No metabolite of triamterene was detected in these tissues. The pharmacokinetics of 14C-triamterene also were investigated. The volume of distribution of the drug was greater in the central compartment (60% of the dose) than in the peripheral compartment (40%). The binding of the drug to skeletal muscle is responsible for the fraction of the dose in the peripheral compartment. Rate constants indicate that slow elimination of triamterene is related to its binding to tissue in the central compartment.
D000818:Animals; D007700:Kinetics; D008297:Male; D008954:Models, Biological; D051381:Rats; D013997:Time Factors; D014223:Triamterene / Q000097:blood / Q000378:metabolism*
D014223:Triamterene