Pharmacokinetic and depletion studies of sarafloxacin after oral administration to eel (Anguilla anguilla)

The pharmacokinetics of sarafloxacin applied by oral gavage at a dose of 15 mg/kg b.w. was studied in eel (Anguilla anguilla) at water temperature of 24 degrees C. Sarafloxacin levels were determined using high performance li quid chromatography with a quantitation limit of 0.07 mu g/ml or gram. The time to peak plasma concentration, T-max, was 12 hr and peak concentration, C-max, was 2.64 mu g/ml. The absorption rate constant (k(a)) was 0.23 hr(- 1) (r=0.996). The drug disposition curve after T-max was fitted to a two-co mpartment open model. The distribution rate constant (alpha) was 0.085 hr(- 1) (r=0.972), and the half-life (t(1/2 alpha)) was 8.15 hr. The elimination rate constant (beta) was 0.023 hr(-1) (r=0.909), and the half-life (t(1/2 beta), was 30.13 hr. The estimated area under the curve, AUG, was 56.7 mu g .hr/ml. The peak concentrations of drug in liver, kidney, muscle, and skin were 13.39 (12 hr), 5.53 (12 hr), 1.82 (24 hr), and 0.78 mu g/g (40 hr), re spectively. The time for sarafloxacin mean levels to fall below detectable limits in the plasma, muscle, and skin were 7 days but for the liver and ki dney were 14 days.