Structural investigation on the effects of the herbs on Clonorchis sinensis in rabbits.

The effects of boiled water extracts of clonorchicidal raw drugs screened by the EPG counts in vivo on the structure of Clonorchis sinensis were investigated. The extracts of Cassia obutusifolia and Dictamnus dasycarpus did not seem to induce the morphological changes of the worms, and in those of Machilus thunbergii and Prunús mume, widening of bladder to lower level of seminal receptacle was visible without any other changes. Those of Inula helenium and Saussurea lappa, however, disclosed regressive and progressive changes as degeneration, atrophy, necrosis, dilatation, etc. of viscera of the worms. The recover rates of the worms from experimentally infected rabbits administered with the extracts of I. helenium and S. lappa for 30 days, beginning at the 3rd day of inoculation, were as low as 2% and 2.8%, respectively.