三苯双脒对小鼠感染3个旋毛虫分离株的疗效观察

Efficacy of Tribendimidine Against Three Isolates of Trichinella spiralis in Mice

目的观察三苯双脒对感染3个分离株旋毛虫小鼠的疗效。方法将144只昆明小鼠随机均分为A组和B组,每组72只。A组小鼠再随机均分为12组,即河南分离株(以下简称河南株)、云南分离株(以下简称云南株)和黑龙江分离株(以下简称黑龙江株)旋毛虫感染组各4组,每组小鼠各感染旋毛虫分离株幼虫200条/只,感染后5 d(即成虫期)分别顿服三苯双脒10、20和30mg/kg,同时设未服药对照组。B组的分组和感染同A组,感染后53 d(即幼虫成囊期)分别灌胃三苯双脒100、200和300mg/(kg.d),1次/d×7d。A组治疗后2d处死,计数小肠内成虫数。B组治疗后10d处死,剖取全部膈肌,经消化液消化后计数幼虫。计算各组平均虫数和减虫率。结果A组中,河南株和云南株各治疗组平均虫数均低于对照组(P<0.01),河南株3个治疗组的减虫率分别为39.0%、57.9%和86.0%,云南株的减虫率分别为34.9%、69.3%和92.2%,分别随服用三苯双脒剂量的增加,减虫率呈增高的趋势,其中30 mg/kg组各有2只鼠被治愈。黑龙江株10 mg/kg组的平均虫数与对照组的差异无统计学意义(P>0.05),其他2个剂量组平均虫数均显著少于对照组(P<0.01),3组的减虫率分别为27.9%、57.4%和60.7%,亦随服用三苯双脒剂量的增加,减虫率呈增高的趋势。B组各治疗组小鼠的平均虫数均低于对照组(P<0.05),河南株的减虫率分别为57.8%、75.4%和87.5%,云南株的分别为74.5%、92.4%和99.1%,黑龙江株的分别为50.5%、53.3%和61.6%。可见3个旋毛虫感染组均随服药剂量的增加,减虫率相应增高。30 mg/kg剂量组中,云南株的减虫率与河南株的和黑龙江株的比较,差异有统计学意义(P<0.05)。结论三苯双脒对小鼠体内3个地域分离株旋毛虫成虫和成囊期幼虫均有一定的疗效,对云南株旋毛虫疗效更明显。

Objective To evaluate the efficacy of tribendimidine （TBD） against 3 geographical isolates of Trichinella spiralis in mice. Methods Isolates of T. spiralis from Henan （hereinafter referred to as HnT.s）, Yunnan （re- ferred to as YnT.s） and Heilongjiang （referred to as HljT.s） were used in the study. 144 Kunming strain mice were divid- ed into 2 groups： 72 mice in group A （adult stage, treatment at 5 d after infection）, and 72 mice in group B （encapsulat- ed larva stage, treatment at 53 d after infection）. Group A was further divided equally into 12 sub-groups. Mice in every 3 sub-groups were each infected orally with 200 T. spiralis larvae of the 3 isolates respectively, and the remained 3 sub- groups served as untreated control. Mice in the 3 sub-groups infected with one isolate were orally treated with TBD at a single dose of 10, 20, and 30 mg/kg, respectively. Group B was treated as group A but with a course of TBD once daily at a dose of 100, 200, and 300 mg/（kg-d） for 7 d, respectively. Mice in group A were sacrificed 2 d post-treatment and adult worms were recovered from the small intestine and counted. Those in group B were sacrificed 10 d after com- pletion of 7 d treatment. The intact diaphragm was removed and digested for collecting larvae. Worm burden and worm reduction of each treated sub-group were calculated and statistically compared with the respective control. Results In group A, the mean worm burden in the treated sub-groups infected with HnT.s and YnT.s were all significantly lower than that of the controls （P〈0.01）, with a mean worm reduction rate of 39.0%, 57.9%, and 86.0% in HnT.s sub-groups, and of 34.9%, 69.3%, and 92.2% in YnT.s sub-groups, respectively, showing an increase with the dosage, 2 mice in each ofthe 30mg/kg sub-groups were cured. The worm burden in the 10 mg/kg of HljEs subgroup was similar to that of the control （P〉0.05）, but was significantly lower in the other 2 sub-groups than that of the controls （P〈0.01）. The worm re- duction rate in the 3 sub-groups was 27.9%, 57.4%, and 60.7%, respectively. In all treated sub-groups of group B, the mean worm burden was significantly lower than that of the controls （P〈0.05）, with a mean worm reduction rate of 57.8%, 75.4%, and 87.5% in HnT.s sub-groups, of 74.5%, 92.4%, and 99.1% in YnT.s sub-groups, and of 50.5%, 53.3%, and 61.6% in HljT.s sub-groups, respectively, with the 3 dosages. Conclusion Tfiberldimidine shows adequate efficacy on Trichinella spiralis adults and on encapsulated larvae of the 3 geographical isolates in mice, with better effect on Yunnan ;isolate.