The effect of salicylate on the biliary excretion of 14C-bishydroxycoumarin in rat.

1. The effect of intravenous sodium salicylate on the biliary excretion of 14C-bishydroxycoumarin ((14)C-BHC) was studied in rats.2. Salicylate (88.9 mg/kg) increased the biliary excretion of (14)C-radioactivity from a control value of 12.3 +/- 2.7% to 29.3 +/- 2.5% of the administered dose in 6 h after injection.3. During the 6 h period, 11% of the dose of radioactivity underwent biliary recycling in the salicylate-treated rats compared to only 6% in the absence of salicylate.4. About 15.3% of the radioactivity excreted in the bile of rats given BHC alone was detected as unchanged BHC, 8.6% was present as BHC-conjugate, conjugates of BHC metabolites accounted for 30.9%, and the remainder consisted of unidentified metabolites.5. Salicylate treatment did not significantly alter the excretory pattern of unchanged BHC and its metabolites.