Pharmacokinetics of furazolidone in orange-spotted grouper, Epinephelus coioides

Abstract

The pharmacokinetics of furazolidone (FZ) was examined in the orange-spotted grouper (Epinephelus coioides) after intravascular, oral and bath administration. FZ contents in blood and tissues were determined by high performance liquid chromatography. The recoveries of the analytical method applied were 102, 102, 94 and 94% for serum, muscle, liver and kidney, respectively. A two-compartment pharmacokinetic model was found in serum through the mean concentrations of FZ, exhibiting a rapid, biphasic decline after an intravascular dose of 0.1 mg/kg at 23°C. The absorption and elimination half-lives of FZ in serum were 0.2 and 3.3 h, respectively. A one-compartment model could be observed from the serum concentration of FZ after an oral dose at 50 mg/kg; the elimination half-lives were found 1.4 and 0.8 h at 23 and 30°C, respectively. During a 24-hour bath period, variable temperatures gave significant effects on rate of absorption and elimination of FZ, while different doses showed different peak concentrations and integrated areas under the concentration-time curve. The bioavailabilities of FZ in the oral and bath applications were 0.4 and 26.4%, respectively. FZ was found mainly distributed in the serum and muscle, rather than in the liver or kidney.