不同吡喹酮给药方案治疗日本血吸虫感染小鼠的结果比较

目的: 观察吡喹酮不同给药时间、不同给药剂量对日本血吸虫感染小鼠生存状况的影响,以及对小鼠血清中可溶性虫卵抗原(SEA)特异性抗体水平的影响。 方法: 90只BALB/c小鼠随机分成5组,感染和治疗1、2、3组,各20只小鼠,以腹部贴壁法感染日本血吸虫尾蚴;剩余10只小鼠作为阴性对照组(Ns)。治疗1、2组均在感染6周时开始治疗,给药剂量分别是300 mg·kg^-1和150 mg·kg-1,连续给药3 d;治疗3组在感染5周开始治疗,给药剂量150 mg·kg^-1,连续给药3 d;治疗2和治疗3组于感染后8周进行第二次治疗,剂量300 mg·kg^-1,连续给药3 d 。整个实验过程对小鼠进行每周进行称重,观察小鼠生存状态的变化。感染后12周、14周、17周对各组小鼠采血,检测血清中SEA特异性IgG抗体的变化。 结果: 感染日本血吸虫6周后,感染和治疗组BALB/c小鼠体重均显著降低;其中感染5周开始给药的治疗3组小鼠体重恢复最快,感染后7周体重就恢复到阴性组水平,小鼠的生存率为100%,治疗后血清SEA特异性IgG值也最低;感染6周开始治疗的两组中,高剂量的治疗1组体重恢复略快于低剂量的治疗2组,但是治疗1组小鼠生存率仅为30%,明显低于治疗2组的65%。治疗1、2组的小鼠血清IgG值比较接近,高于治疗3组。 结论: 小鼠感染日本血吸虫后,最佳治疗时间应不晚于感染5周,在感染5周之前给予治疗能大大降低感染小鼠的死亡数量,治疗效果最显著;对于感染6周后的小鼠,应该采用首次低剂量服药治疗,可明显改善感染小鼠的生存率。治疗时间提前有助于鼠血清抗体水平回落。

Objective: To investigate the effect of different praziquantel dosage regimens on survival state,as well as soluble egg antigen(SEA)specific IgG antibodies of BALB/c mice infected by S.japonicum. Methods: A total of 90 BALB/c mice were randomly divided into five groups:infection and treatment groups—group 1,group 2,and group 3,with 20 mice in each group which were experimentally infected with S.japonicum cercaria though abdominal wall; the remaining ten mice were enrolled in the negative control group(Ns). At 6 weeks after infection,mice in treatment groups 1 and 2 were given praziquantel continuously for 3 days at doses of 300 mg·kg^-1 and 150 mg·kg^-1,respectively.Mice in treatment group 3 were given praziquantel continuously for 3 days at dose of 150 mg·kg^-1at 5 weeks after infection.Mice in treatment groups 2 and 3 were given praziquantel 3days continuously again at dose of 300 mg·kg^-1 at 8 weeks after infection.The mice were weighed every week.The SEA-specific IgG level was detected by ELISA at 12,14 and 17 weeks after infection. Results: The mice's weights of infection and treatment groups were significantly lower than that of the negative control group at 6 weeks after infection.The body weights of mice in treatment group 3 recovered the fastest,which returned to the same level of the negative control group at 7 weeks after infection.The survival rate of treatment group 3 was 100%,and the SEA-specific IgG value was the lowest among all the groups.In the groups treated at 6 weeks after infection,the body weight of treatment group 1 with high-dose praziquantel recovered slightly faster than that of treatment group 2 with low-dose praziquantel,but the survival rate of treatment group 1 was 30%,significantly lower than 65% of treatment group 2.The SEA-specific IgG levels of treatment groups 1 and 2 were almost the same,but both higher than that of treatment group 3. Conclusion: The optimal treatment time should be no later than 5 weeks after infection for BALB/c mice infected experimentally by S.japonicum.When being treated with praziquantel at 5 weeks after infection,the number of the dead infected mice can be greatly reduced,compared with that of those being treated at 6 weeks after infection.The initial low-dosed praziqutantel treatment should be used for mice infected with S.japonicum for 6 weeks,which can significantly improve the survival rate of infected mice.Early treatment time can help to reduce the SEA-specific IgG level of infected mice.