Rondelaud D, Vignoles P, Dreyfuss G
UPRES EA no. 3174/USC INRA, Faculty of Medicine and Faculty of Pharmacy, 87025 Limoges, France.
J Helminthol. 2007 Sep;81(3):317-22. doi: 10.1017/S0022149X07818542.
Histological investigations in Galba truncatula naturally or experimentally co-infected with Fasciola hepatica and Paramphistomum daubneyi were carried out to study parasite development and the responses of the digestive gland and kidney of snails, as larval forms of these digeneans often use these two sites for their growth within the snail's body. The number of live rediae per snail ranged from 2.4 to 4.2 for the dominating parasite (it developed in the digestive gland) and was less than 2.0 for the other species. When the dominating species was F. hepatica, most snails harboured cercariae-containing rediae; if this parasite was P. daubneyi, procercariae-containing rediae with or without free procercariae were observed in most snails. In contrast, most rediae of the other species were immature. The pathology caused by the dominating species in the digestive gland was greater than that recorded in the kidney, where the other parasite was generally located. The most frequent tissue lesions in the digestive gland were generalized epithelial necrosis and epithelial reconstitution. In the kidney, multifocal epithelial necrosis was frequently observed, particularly when P. daubneyi was the dominating species. The frequencies of lesions in the digestive gland agreed with percentages reported by our team in other snails mono-infected with F. hepatica or P. daubneyi. In contrast, multifocal necrosis in the kidney was clearly greater in the present study and this finding might be explained by assuming that a sufficient number of free larvae within the snail would be necessary for the development of epithelial necrosis in the whole kidney.
对自然感染或实验感染肝片吸虫和道氏双腔吸虫的截口圆扁螺进行了组织学研究，以探讨寄生虫的发育情况以及蜗牛消化腺和肾脏的反应，因为这些复殖吸虫的幼虫通常利用这两个部位在蜗牛体内生长。对于占主导地位的寄生虫（它在消化腺中发育），每只蜗牛体内活雷蚴的数量在2.4至4.2之间，而另一种寄生虫的数量则少于2.0。当占主导地位的物种是肝片吸虫时，大多数蜗牛体内含有尾蚴的雷蚴；如果这种寄生虫是道氏双腔吸虫，在大多数蜗牛体内观察到含有原尾蚴的雷蚴，有的还带有游离的原尾蚴。相比之下，另一种寄生虫的大多数雷蚴未成熟。占主导地位的物种在消化腺中引起的病变比在肾脏中记录的病变更严重，而另一种寄生虫通常位于肾脏中。消化腺中最常见的组织病变是广泛性上皮坏死和上皮重建。在肾脏中，经常观察到多灶性上皮坏死，特别是当道氏双腔吸虫是占主导地位的物种时。消化腺中的病变频率与我们团队报道的其他单感染肝片吸虫或道氏双腔吸虫的蜗牛中的百分比一致。相比之下，本研究中肾脏的多灶性坏死明显更严重，这一发现可以通过假设蜗牛体内有足够数量的游离幼虫是整个肾脏上皮坏死发展的必要条件来解释。
