FIG. 3.

Intestinal (A) and biliary (B) clearances of [¹⁴C]grepafloxacin and its metabolites after i.v. administration in rats. Five hundred microliters of isotonic MES buffer was administered into 10-cm loops of duodenum and ileum, and then [¹⁴C]grepafloxacin was administered intravenously at a dose of 34 nmol per animal. Bile was collected via a cannula for 60 min, and at the end of the experiment, the intestinal loops were removed and the solution in each loop was collected. The clearance values were estimated by dividing the [¹⁴C]grepafloxacin recovered in the intestinal loops or bile by the area under the plasma concentration-time curve from time zero to 60 min. Open and closed columns, means ± standard errors of the means for SDRs and EHBRs, respectively; *, significant difference between SDRs and EHBRs by Student’s t test (P < 0.05).