Discharge Mechanism of the Nematocysts of Pelagia noctiluca

  • A. Salleo
Part of the Proceedings in Life Sciences book series (LIFE SCIENCES)


The nematocysts are complex organelles, contained in specialized cells, the nematocytes. Under adequate stimulus (Lubbock 1979; Tardent et al. 1980; Ertman and Davenport 1981) the nematocysts eject a threat that, in turn, either adheres to or penetrates into the prey, injecting the venomous substances contained into the capsule fluid. The nematocyst is generally believed to be formed as a secretory product of Golgi apparatus (Cormier and Hessinger 1980) although such an interpretation has been recently questioned (Holstein 1981). The complex process of differentiation which produces the three layers of the capsule wall and the thread has been recently described by Holstein (1981). The cnidocil apparatus seems to be the sensory receptor that elicits the discharge in the intact system in situ (Cormier and Hessinger 1980). Nevertheless, the discharging capacity is retained in isolated nematocysts, although it is less prompt than it is in situ. Since quantitative and detailed data concerning the effectiveness of stimuli cannot be obtained on nematocysts in situ, isolated capsules are frequently employed with the aim to investigate the mechanism of discharge, which, in spite of the numerous attempts to elucidate it, is still uncertain.


Methylene Blue Discharge Capacity Neutral Salt Capsule Wall Polyvalent Cation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Blanquet R (1968) Properties and composition of the nematoeysts toxin of the sea anemone Aiptasia pallida. Comp Biochem Physiol 25: 893–902PubMedCrossRefGoogle Scholar
  2. Blanquet R (1970) Ionic effects on discharge of the isolated and in situ nematoeysts of the sea anemone Aiptasia pallida: a possible role of calcium. Comp Biochem Physiol 35: 451–61CrossRefGoogle Scholar
  3. Blanquet R, Lenhoff HM (1966) A disulfide-linked collagenous protein of nematocyst capsules. Science (Wash DC) 154: 152–153CrossRefGoogle Scholar
  4. Calabrese L, Salleo A, Alfa M, La Spada G (1983) The release of a glutamate rich protein from Pelagia noctiluca nematoeysts in the discharge process. 5th Conference of the European Society for Comparative Physiology and Biochemistry. Taormina (Italy) September, pp 5–8, 53–54Google Scholar
  5. Cignitti M, Figura M, Marchetti M, Salleo A (1970) Electrokinetic effect in mechanoeleetrical phenomenology of the bone. Arch Fisiol 68: 232–249Google Scholar
  6. Cormier SM, Hessinger DA (1980) Cnidocil apparatus: sensory receptor of Physalia nematocytes. J Ultrastruct Res 72: 13–19PubMedCrossRefGoogle Scholar
  7. Diamond JM, Wright EM (1969) Biological membranes: the physical basis of ion and nonelectrolyte selectivity. Ann Rev Physiol 31: 581–646CrossRefGoogle Scholar
  8. Ertman SC, Davenport D (1981) Tentacular nematocyte discharge and “self-recognition” in Anthopleura elegantissima (Brandt). Biol Bull (Woods Hole) 161: 366–370CrossRefGoogle Scholar
  9. Hamon M (1955) Cytochemical research on coelenterate nematoeysts. Nature (Lond) 4477: 357CrossRefGoogle Scholar
  10. Holstein T (1981) The morphogenesis of nematocytes in Hydra and Forskalia: an ultrastructural study. J Ultrastruct Res 75: 276–290PubMedCrossRefGoogle Scholar
  11. Lubbock R (1979) Chemical recognition and nematocyte excitation in a sea anemone. J Exp Biol 83: 283–292Google Scholar
  12. Lubbock R, Amos WB (1981) Removal of bound calcium from nematoeysts causes discharge. Nature (Lond) 290: 500–501CrossRefGoogle Scholar
  13. Lubbock R, Gupta BL, Hall TA (1981) Novel role of calcium in exocytosis: mechanism of nematoeysts discharge as shown by X-ray microanalysis. Proc Natl Acad Sci USA 78: 3624–3628PubMedCrossRefGoogle Scholar
  14. Mariscal RN (1974) Nematoeysts. In: Muscatine L and Lenhoff HM (eds) Coelenterate biology. Academic, London, p 129Google Scholar
  15. Mariscal RN (1980) The elemental composition of nematoeysts as determined by X-ray microanalysis. In: Tardent P and Tardent R (eds) Developmental and cellular biology of coelenterates. Elsevier/North Holland Biomedical, p 337Google Scholar
  16. Mariscal RN, Lenhoff HM (1969) Effect of disulfide reducing agent on coelenterate nematocyst capsule. Experientia (Basel) 25: 330–331CrossRefGoogle Scholar
  17. Phillips JH (1956) Isolation of active nematoeysts of Metridium senile and their chemical compostion. Nature (Lond) 178: 932CrossRefGoogle Scholar
  18. Salleo A, La Spada G, Alfa M (1983) Blockage of trypsin-induced discharge of nematoeysts of Pelagia noctiluca by Ca2+. Mol Physiol 3: 89–97Google Scholar
  19. Salleo A, La Spada G, Falzea G, Denaro MG (to be published 1983a ) Discharging effect of anions and inhibitory effect of divalent cations on isolated nematoeysts of Pelagia noctiluca. Mol PhysiolGoogle Scholar
  20. Salleo A, La Spada G, Falzea G, Denaro MG (to be published 1983b) pH-induced collapse of the capsular wall in isolated nematoeysts oí Pelagia noctiluca. Cell Mol BiolGoogle Scholar
  21. Svendsen KH, Thomson G, Wismer-Pedersen J (1983) Absolute values of lenght-tension relations from collagen fibers of different ages and at different pH values. Mol Physiol 3: 237–247Google Scholar
  22. Szent-Gyorgyi A (1951) A new method for the preparation of actin. J Biol Chem 192: 361–369PubMedGoogle Scholar
  23. Tardent P, Honneger T, Baenninger R (1980) About the function of stenotheles in Hydra attenuata pall In: Tardent P and Tardent R (eds) Developmental and cellular biology of coelenterates. Elsevier/North Holland Biomedical, p 331Google Scholar
  24. Wood RL, Novak P (1982) The anchoring of nematoeysts and nematocystes in the tentacles of Hydra. J Ultrastruct Res 81: 104–116PubMedCrossRefGoogle Scholar
  25. Yanagita TM, Wada T (1953) Discharge-inducing concentration of acids and bases for the nematoeysts of sea anemone. Nat Sci Rep Ochanomizu Univ 4: 112–118Google Scholar
  26. Yanagita TM, Wada T (1954) Effects of trypsin and thioglycollate upon the nematoeysts of the sea anemone. Nature (Lond) 4395: 171CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1984

Authors and Affiliations

  • A. Salleo
    • 1
  1. 1.Institute of General PhysiologyUniversity of MessinaMessinaItaly

Personalised recommendations