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A comparative study of the two alternative larval forms of Hymenolepis nana, the dwarf tapeworm, with special reference to the process of excystment

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Summary

Studies of the cysticercoids of Hymenolepis nana from insects and from mouse villi revealed important differences in cyst structure and function. The insect form resists low pH unless treated with bile salts which render the cyst permeable and reduce infectivity to mice. Bile salts are not essential for scolex activation. Activation is inhibited by pH 2.5 and under and by 1% succinic acid up to pH 4.0. The importance of scolex immobility and energy conservation in relation to cyst impermeability is discussed. The villus cysticercoid has no special insulating layer. It is vulnerable to low pH and cannot infect mice orally. Bile salts are without effect and excystment occurs unaided by external agents. The structural differences between the two forms revealed by the electron microscope may be attributed to changes in the relative rates of development of the various tissues.

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References

  • Allison, V. F., Uberlaker, J. E., Cooper, N. B.: The fine structure of the cysticercoid of Hymenolepis diminuta. II. The inner wall of the capsule. Z. Parasitenk. 39, 137–147 (1972)

    Google Scholar 

  • Berntzen, A. K.: Continuous axenic culture of the successive stages of the life cycle of Hymenolepis nana. J. Parasit. 56, II Part 2, 397 (1970)

    Google Scholar 

  • Caley, J.: The functional significance of scolex retraction and subsequent cyst formation in the cysticercoid larva of Hymenolepis microstoma. Parasitology 68, 207–227 (1974)

    Google Scholar 

  • Campbell, W. C.: The efficacy of surface-active agents in stimulating the evagination of cysticerci in vitro. J. Parasit. 49, 81–84 (1963)

    Google Scholar 

  • Glassman, H. N.: Surface active agents and their application in bacteriology. Bact. Rev. 12, 105–148 (1948)

    Google Scholar 

  • Goodchild, C. G., Davis, B. O.: H. microstoma cysticercoid activation and excystation in vitro (Cestoda). J. Parasit. 58, 735–741 (1972)

    Google Scholar 

  • Henry, H., Stacey, M.: Histochemistry of the gram-staining reaction of micro-organisms. Nature (Lond.) 151, 671 (1943)

    Google Scholar 

  • Heyneman, D.: Studies on helminth immunity. III. Experimental verification of autoinfection from cysticercoids of Hymenolepis nana in the white mouse. J. infect. Dis. 109, 10–18 (1961)

    Google Scholar 

  • Hunninen, A. V.: Studies on the life history and host-parasite relations of Hymenolepis fraterna (H. nana var. fraterna) in white mice. Amer. J. Hyg. 22, 414–443 (1935)

    Google Scholar 

  • Jacobsen, N. S., Fairbairn, D.: Lipid metabolism in helminth parasites. III. Biosynthesis and interconversion of fatty acids by H. diminuta (Cestoda). J. Parasit. 53, 355–361 (1967)

    Google Scholar 

  • Rothman, A. H.: Studies on the excystment of tapeworms. Exp. Parasit. 8, 336–364 (1959)

    Google Scholar 

  • Rycke, P. H. de, Grembergen, G. van: Study on the evagination of Cysticercus pisiformis. Z. Parasitenk. 27, 341–349 (1966)

    Google Scholar 

  • Smith, C F: Attempts at in vitro cultivation of the fowl cestode Raillietina cesticillus. J. Parasit. 40, Suppl. 41–42 (1955)

    Google Scholar 

  • Smyth, J. D.: The Physiology of Cestodes. Edinburgh: Oliver and Boyd 1969

    Google Scholar 

  • Smyth, J. D., Haslewood, G. A. D.: The biochemistry of bile as a factor in determining host specificity in intestinal parasites, with particular reference to Echinococcus granulosus. Ann. N. Y. Acad. Sci. 113, 234–260 (1963)

    Google Scholar 

  • Voge, M., Heyneman, D.: Development of Hymenolepis nana and H. diminuta in the intermediate host Tribolium confusum. Univ. Calif. Publ. Zool. 59, 549–580 (1957)

    Google Scholar 

  • Voge, M., Heyneman, D.: Effect of high temperature on the larval development of Hymenolepis nana and Hymenolepis diminuta. J. Parasit. 44, 249–260 (1958)

    Google Scholar 

  • Waele, A. de: Investigation on the biochemical mechanism of the influence of bile salts, acetylcholine and choline on the evagination of cysticerci of the cestodes. Med. roy. vlaam. Acad., Kl. Wetensch. 1, 3–19 (1940)

    Google Scholar 

  • Waele, A. de, Dedeken, L.: Le phénoménon de l'évagination chez Cysticercus bovis et la migration du parasite chez l'homme. Mém. Mus. roy. Hist. nat. belg. 2, 369–373 (1936)

    Google Scholar 

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Author notes

  1. Jennifer Caley

    Present address: Bratha Field Study Centre, Ambleside, Cumbria, UK

Authors and Affiliations

  1. School of Biological Sciences, University of East Anglia, Norwich

    Jennifer Caley

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  1. Jennifer Caley
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Caley, J. A comparative study of the two alternative larval forms of Hymenolepis nana, the dwarf tapeworm, with special reference to the process of excystment. Z. F. Parasitenkunde 47, 217–235 (1975). https://doi.org/10.1007/BF00418205

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  • DOI: https://doi.org/10.1007/BF00418205

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