On comparative pharmacokinetic of Enrofloxacin in Hemolymph of Chinese mitten-handed crab,Eriocheir sinensis

Several comparative pharmacokinetic data such as absorption,distribution and metabolism had been studied on enrofloxacin(ENR) in Chinese mitten-handed crab,Eriocheir sinensis with different water temperature,dose and dosage regime(oral administration and intramuscular injection).Results indicated that the hemolymph concentration-time data of Enrofloxacin in Eriocheir sinensis were best described by a two-compartment open model under different conditions.The main pharmacokinetics parameters by intramuscular administration with 10 mg/kg b.w.at 16 ℃: AUC 96.818mg /(L·h),Cmax 6.54 μg/mL,t1/2α 0.851h,t1/2β 95.415 h;the main pharmacokinetics parameters by intramuscular administration with 10 mg/kg b.w.at 25 ℃: AUC 168.457 mg /(L·h),Cmax 7.12 μg/mL,t1/2α 0.58h,t1/2β 88.833 h;the main pharmacokinetics parameters by intramuscular administration with 20 mg/kg b.w.at 25 ℃: AUC 155.612 mg /(L·h),Cmax 11.045 μg/mL,t1/2α 5.239 h,t1/2β 88.378 h;the main pharmacokinetics parameters by oral administration with 10 mg/kg b.w.at 25 ℃: AUC 86.525 mg /L·h,Cmax 3.469 μg/mL,t1/2α8.071 h,t1/2β 61.842h.Results showed that the main pharmacokinetic parameters under different conditions were significantly different.The active metabolite ciprofloxacin(CIP) was checked in hemolymph of Eriocheir sinensis in all experiments,but all compartment models were not suitable for concentration-time data,and the concentration was very low,which indicated the poor capability of Eriocheir sinensis metabolizing enrofloxacin into ciprofloxacin.