盐酸沙拉沙星在凡纳滨对虾体内药动学与生物利用度

采用RP-HPLC法研究了在盐度33、水温（28.0±1.0）℃的自然海水中盐酸沙拉沙星单剂量围心腔注射（剂量10 mg·kg-1）和单次药饵投喂（剂量30 mg·kg-1）给药后在凡纳滨对虾（Litopenaeus vannamei）体内的药动学与生物利用度。围心腔注射给药后，血淋巴中药时曲线较适合用二室模型来拟合，而药饵投喂给药后血淋巴中药时曲线较适合采用一级吸收二室模型来拟合。药饵给药下盐酸沙拉沙星在凡纳滨对虾体内的生物利用度（F）为61.6%。药饵投喂给药下大量药物分布到了肝胰腺，肝胰腺血药峰浓度（Cmax）和AUC0-t分别是血淋巴的24.4倍和18.7倍，分别是肌肉的51.9倍和62.0倍；药物在肝胰腺和肌肉中消除都很快，分别在给药后5 d 和36 h低于0.1 mg·kg-1。由此可见，盐酸沙拉沙星药饵给药下吸收好，达峰值高和生物利用度好，且在肌肉和肝胰腺组织中消除快，是较为理想的防治对虾细菌性疾病的抗菌药物。

Pharmacokinetics and bioavailability of sarafloxacin hydrochloride in Litopenaeus vannamei

We investigated the pharmacokinetics and bioavailability of sarafloxacin hydrochloride in Litopenaeus vannamei following intra-sinus injection （10 mg？kg-1） and oral administration （30 mg？kg-1） using the RP-HPLC. The shrimps were kept in seawater with salinity of 33 and at temperature of （28.0±1.0） ℃. The concentration-time curves of haemolymph sarafloxacin hydrochloride after intra-sinus injection and oral adminstration were best described by two-compartment model and two-compartment model with first absorption, respectively. After oral adminstration, the bioavailability （F） of sarafloxacin hydrochloride was 61.6%, and the concentration of sarafloxacin hydrochloride in hepatopancreas was 24.4 and 51.9 times higher than that in hemolymph and muscle, respectively, while the AUC0-t of hepatopancrea was 18.7 and 62.0 times higher than that in hemolymph and muscle, respectively. However, the sarafloxacin hydrochloride was faster eliminated in hepatopancreas and muscle, the reside concentration being less than 0.1 mg？kg-1 in 36 h for muscle and in 5 d for hepatopancreas after oral administration. Since sarafloxacin hydrochloride has good absorption and high bioavailability with faster elimination in hepatopancreas and muscle, it is an ideal antimicrobial agent for prevention and treatment of shrimp bacterial diseases.