磺胺二甲氧嘧啶钠在斑点叉尾鮰体内的残留及其消除规律

Residue and elimination of sulphadimethoxine-sodium in tissues of Ictalurus punctatus

在(19±1)℃水温下,以200mg/kg的剂量对斑点叉尾鮰单次口灌磺胺二甲氧嘧啶钠(SDM-Na),采用HPLC方法研究了SDM-Na在斑点叉尾鮰体内的残留及消除规律。研究结果表明,本试验的回收率在79%～93%之间,最低检测限为0.01μg/g,日间和日内精密度(RSD)均小于5%。血浆中药物代谢符合二室模型,模型为C=36.68e-0.14t+18.12e-0.05t-54.8e-0.33t。主要药代动力学参数为:分布半衰期为4.85h,药峰时间为5.38h,峰值浓度为21.42μg/mL。肌肉中的药物含量在4h达到最大值17.93μg/g,肝脏中的药物含量在8h达到最大值10.43μg/g,肾脏中的药物含量在8h达到最大值11.61μg/g。在停药120h时血液、肌肉、肝脏、肾脏组织中的含量均低于国家残留标准(100μg/kg)。在本试验条件下,斑点叉尾鮰的的建议休药期应大于5d。

The residue and elimination of sulfadimethoxine-sodium were estimated in tissues of channel catfish after a single oral administration at the dose of 200 mg /kg （body weight） at 19 ± 1 ℃ ,the SDM-Na concentration in tissues was detected by HPLC method.The results showed that the recoveries were in the range of 79%-93% ,the detection limit was 0.01 μg /g,the RSD of intra-day and inter-day precision was less then 5% .The plasma concentration-time course of SDM-Na could be described by a twocompartment model,C = 36.68e-0.14t ＋ 18.12e-0.05t-54.8e-0.33t.The main pharmacokinetic parameters were as follows： the distribution half-life of the drug was found to be 4.85 h,peak time was 5.38 h,peak concentration was 21.42 μg / mL.The peak concentration in muscle was 17.93 μg /g at 4 h.The peak concentration in liver was 10.43 μg /g at 8 h,the peak concentration in kidney was 11.61 μg /g at 8 h.The residues were lower than the national standard （100 μg / kg） after 120 h in plasma,muscle,liver,kidney.It suggested that the withdrawal time of SDM-Na should be more then 5 days under this experimental condition.