Dixon B R, Arai H P
Department of Biological Sciences, University of Calgary, Alberta, Canada.
J Parasitol. 1991 Oct;77(5):769-74.
Anthelmintic efficacy studies typically involve direct counts of worms remaining in the host shortly after drug treatment. Few such studies, however, have considered the phenomenon of tapeworm destrobilation when determining effective dosages. The present study reports on the frequency of drug-induced destrobilation and the subsequent regeneration of Hymenolepis diminuta in rats following treatment with niclosamide or praziquantel and its implications with respect to the apparent efficacy of these anthelmintics. Drug efficacies very similar to those reported in the literature were determined upon examination of infected animals 24 hr posttreatment. Small regenerating worms were, however, observed in the small intestine of rats 8 days after treatment, indicating that destrobilated worms were present, but overlooked, during the initial examination. Within several days posttreatment, destrobilated worms can regenerate to a size that is readily apparent in the gut contents, allowing the effective dosage to be determined with much greater confidence. Due to the demonstrated ability of these destrobilated worms to regenerate to the gravid state, it is imperative that a fully effective anthelmintic dosage be determined and administered.
驱虫效果研究通常涉及在药物治疗后不久直接计数宿主体内残留的蠕虫。然而，很少有此类研究在确定有效剂量时考虑绦虫节片脱落的现象。本研究报告了用氯硝柳胺或吡喹酮治疗大鼠后，微小膜壳绦虫药物诱导节片脱落的频率及其随后的再生情况，以及这对这些驱虫药表观疗效的影响。在治疗后24小时检查感染动物时，确定的药物疗效与文献报道的非常相似。然而，在治疗后8天，在大鼠小肠中观察到小型再生蠕虫，这表明在初次检查时存在节片脱落的蠕虫，但被忽视了。在治疗后的几天内，节片脱落的蠕虫可以再生到在肠道内容物中很容易看到的大小，从而能够更有把握地确定有效剂量。由于已证明这些节片脱落的蠕虫能够再生到妊娠状态，因此必须确定并施用完全有效的驱虫剂量。
