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Neuromuscular physiology of Grillotia erinaceus metacestodes (Cestoda: Trypanorhyncha) in vitro

Published online by Cambridge University Press:  06 April 2009

S. M. Ward
Affiliation:
Department of Biology, University of Ulster, Shore Road, Newtownabbey, Co. Antrim BT37 0QB, Ireland
J. M. Allen*
Affiliation:
Department of Biology, University of Ulster, Shore Road, Newtownabbey, Co. Antrim BT37 0QB, Ireland
G. McKerr
Affiliation:
Department of Biology, University of Ulster, Shore Road, Newtownabbey, Co. Antrim BT37 0QB, Ireland
*
To whom correspondence should be addressed

Summary

Isometric tension recordings and the single sucrose-gap technique were used to record mechanical and electrical activity from Grillotia erinaceus metacestodes in vitro. Both complete preparations and those cut longitudinally (to allow access of the bathing medium to the region of the somatic muscle) showed spontaneous contractions of frequency ≃ 1/min in Hanks’ Balanced Salt Solution (HBSS) at 13 °C. Changing the pH, temperature or osmolarity of the HBSS did not improve the activity but rather abolished it at extremes of these variables, so confirming the adequacy of the experimental environment for further work. The neurotoxin tetrodotoxin (TTX; 3 × 10−6 M) failed to abolish or modify these spontaneous contractions although excitatory and inhibitory responses to 5-hydroxytryptamine (5-HT) and acetylcholine (ACh) respectively were demonstrated. Electrical recordings showed that spontaneous contractions were mediated by slow membrane depolarizations upon which spike-like potentials were often superimposed. 5-HT was shown to mediate its excitatory effect via membrane depolarization and an increase in the frequency of both slow depolarization and spikes. In contrast, inhibition by ACh was accompanied by membrane hyperpolarization and loss of all regenerative electrical activity. Electric field stimulation of the preparation using a range of stimulus parameters failed to demonstrate a functional motor innervation to the somatic muscle.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1986

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References

Bolton, T. B. (1979). Mechanisms of action of transmitters and other substances on smooth muscle. Physiological Reviews 59, 606718.CrossRefGoogle ScholarPubMed
Coburn, R. F., Ohba, M. & Tomita, T. (1975). Recording of intracellular electrical activity with the sucrose gap method. In Methods in Pharmacology, vol. 3. Smooth Muscle (ed. Daniel, E. E. and Patton, D. M.), pp. 231–45. New York and London: Plenum Press.Google Scholar
Duckles, S. P. (1980). Transmural electrical stimulation: distinguishing between activation of nerves and smooth muscle. In Vascular Neuroeffector Mechanisms (ed. Bevan, J. A.Godfraind, T.Maxwell, R. A. and Vanhoutte, P. M.), pp. 33–5. New York: Raven Press.Google Scholar
Duguid, A. M. E. & Heathcote, R. St A. (1950). The action of drugs in vitro on cestodes. II. Non-anthelmintic drugs. Archives Internationales de Pharmacodynamie et de Thérapie 84, No. 23, 159–75.Google ScholarPubMed
Fairweather, I. & Threadgold, L. T. (1983). Hymenolepis nana: the fine structure of the adult nervous system. Parasitology 86, 89103.CrossRefGoogle ScholarPubMed
Hess, E. (1980). Ultrastructural study of the tetrathyridium of Mesocestoides corti: tegument and parenchyma. Zeitschrift für Parasitenkunde 61, 135–59.CrossRefGoogle ScholarPubMed
Lumsden, R. D. & Byram, J. (1967). The ultrastructure of cestode muscle. Journal of Parasitology 53, 326–41.CrossRefGoogle ScholarPubMed
Lumsden, R. D. & Hildreth, M. B. (1983). The fine structure of adult tapeworms. In Biology of the Eucestoda, vol. 1 (ed. Arme, C. and Pappas, P. W.), pp. 177233. London: Academic Press.Google Scholar
McKerr, G. (1985). The fine structure and physiology of a trypanorhynch tapeworm Grillotia erinaceus. Ph.D. thesis, Queen's University, Belfast, Northern Ireland.Google Scholar
Mettrick, D. F. & Cho, C. H. (1981). Migration of Hymenolepis diminuta (Cestoda) and changes in 5-hydroxytryptamine (Serotonin) levels in the rat host following parenteral and oral 5-hydroxytryptamine administration. Canadian Journal of Physiology and Pharmacology 59, 281–6.CrossRefGoogle ScholarPubMed
Paasonen, M. K. & Varitiainen, A. (1958). Pharmacological studies on the body wall musculature of cat tapeworm (Taenia taeniaeformis). Acta pharmacologica et toxicologica 15, 2936.CrossRefGoogle ScholarPubMed
Read, C. P., Douglas, L. T. & Simmons, J. E. jr (1959). Urea and osmotic properties of tapeworms from elasmobranchs. Experimental Parasitology 8, 5875.CrossRefGoogle ScholarPubMed
Shield, J. M. (1969). Dipylidium caninum, Echinococcus granulosus and Hydatigera taeniaeformis: histochemical identification of cholinesterases. Experimental Parasitology 25, 217–31.CrossRefGoogle ScholarPubMed
Shield, J. M. (1971). Histochemical localisation of monoamines in the nervous system of Dipylidium caninum (Cestoda) by the formaldehyde fluorescence technique. International Journal for Parasitology 1, 135–8.CrossRefGoogle ScholarPubMed
Smith, H. W. (1936). The retention and physiological role of urea in the elasmobranchs. Biological Reviews 11, 4982.CrossRefGoogle Scholar
Stämpfli, R. (1954). A new method for measuring membrane potentials with external electrodes. Experientia 10, 508–9.CrossRefGoogle ScholarPubMed
Sukhedo, M. V. K., Hsu, S. C., Thompson, C. S. & Mettrick, D. F. (1984). Hymenolepis diminuta: behavioural effects of 5-hydroxytryptamine, acetylcholine, histamine and somatostatin. Journal of Parasitology 70, 682–8.CrossRefGoogle Scholar
Sukhedo, M. V. K. & Mettrick, D. F. (1984). Migrational responses of Hymenolepis diminuta to surgical alteration of gastrointestinal secretions. Parasitology 88, 421–30.CrossRefGoogle Scholar
Thompson, C. S. & Mettrick, D. F. (1984). Neuromuscular physiology of Hymenolepis diminuta and Hymenolepis microstoma (Cestoda). Parasitology 89, 567–78.CrossRefGoogle Scholar
Tomita, T. (1981). Electrical activity (spikes and slow waves) in gastrointestinal smooth muscles. In Smooth Muscle: an Assessment of Current Knowledge (ed. E., Bülbring, Brading, A. F., Jones, A. W. and Tomita, T.), pp. 171–97. London: Edward Arnold.Google Scholar
Ward, S. M., Allen, J. M. & McKerr, G. (1984). Fine structure and innervation of attachment muscle in the tapeworm Grillotia erinaceus. Journal of Microscopy 19 (6), (Suppl.).Google Scholar
Webb, R. A. (1982). Innervation of muscle in the cestode Hymenolepis microstoma. ICOPA abstract, Molecular and Biochemical Parasitology (Suppl.), 151–2.Google Scholar