Hawdon J M, Volk S W, Pritchard D I, Schad G A
Department of Pathobiology, University of Pennsylvania, Philadelphia.
J Parasitol. 1992 Dec;78(6):1036-40.
Third-stage infective larvae of the canine hookworm Ancylostoma caninum resume feeding in vitro in response to several stimuli. Experiments were conducted to characterize the in vitro feeding behavior of several hookworm species. Reduced glutathione and, to a lesser extent, canine and human serum stimulated third-stage larvae of Ancylostoma duodenale to resume feeding. Glutathione-induced feeding reached a maximum by 16 hr and was concentration-dependent between 0- and 15-mM glutathione. Oxidized glutathione and the reducing agents dithiothreitol and L-cysteine failed to induce feeding, suggesting that reducing conditions alone were not stimulatory. Serum incubated with glutathione was the most efficient stimulus for Ancylostoma ceylanicum, Ancylostoma braziliense, and Ancylostoma tubaeforme larvae, whereas Uncinaria stenocephala larvae responded best to canine serum alone. Necator americanus larvae did not resume feeding in response to glutathione, serum, glutathione plus serum, or linoleic acid (0.1-10 mM). These differences in feeding behavior suggest that generalizations concerning hookworm biology must be interpreted cautiously.
犬钩虫——犬弓首线虫的第三期感染性幼虫会对多种刺激做出反应，在体外恢复取食。开展了多项实验以表征几种钩虫的体外取食行为。还原型谷胱甘肽以及在较小程度上，犬血清和人血清会刺激十二指肠钩口线虫的第三期幼虫恢复取食。谷胱甘肽诱导的取食在16小时时达到最大值，并且在0至15毫摩尔的谷胱甘肽浓度范围内呈浓度依赖性。氧化型谷胱甘肽以及还原剂二硫苏糖醇和L-半胱氨酸均未能诱导取食，这表明仅还原条件并无刺激作用。与谷胱甘肽一起孵育的血清对锡兰钩口线虫、巴西钩口线虫和管状钩口线虫幼虫而言是最有效的刺激物，而窄头钩虫幼虫对单独的犬血清反应最佳。美洲板口线虫幼虫不会因谷胱甘肽、血清、谷胱甘肽加血清或亚油酸（0.1至10毫摩尔）而恢复取食。这些取食行为上的差异表明，有关钩虫生物学的一般性结论必须谨慎解读。
