Advertisement

Acta Biologica Hungarica

, Volume 55, Issue 1–4, pp 239–249 | Cite as

Why the Ovotestis of Helix Aspersa is Innervated

  • R. ChaseEmail author
  • T. Antkowiak
  • E. Geoffroy
  • D. Weatherill
Article

Abstract

Although Schmalz described the innervation of the ovotestis in pulmonate snails as early as 1914, no functions have been attributed to it. In H. aspersa, the intestinal nerve branches profusely within the ovotestis and terminates in the walls of the acini and in the sheath surrounding the early portion of the hermaphroditic duct. We found both sensory and motor functions for this innervation. Significantly, there is a tonic sensory discharge generated by the mechanical pressure of growing oocytes, and the level of tonic afferent activity is strongly correlated with the number of ripe oocytes; this is probably a permissive signal that gates ovulation.

Tactile stimulation of the ovotestis causes a phasic sensory discharge and a pronounced cardio activation. Also, an efferent discharge is elicited in the ovotestis branch of the intestinal nerve. To study the motor consequences of efferent activity, the ovotestis branch was electrically stimulated. We found that such stimulation evokes peristaltic contractions of the initial portion of the hermaphroditic duct and increases beat frequencies of the cilia that line the interior of the duct. These effects could facilitate the transport of oocytes down the duct. Still other functions of afferent activity are implied by changes in the spontaneous activity of mesocerebral cells following nerve stimulation.

Putative sensory neurons and putative motoneurons have been identified in the visceral and right parietal ganglia.

Keywords

Ovotestis ovulation oviposition oocytes snails 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Aguado, L. I. (2002) Role of the central and peripheral nervous system in the ovarian function. Microsc. Res. Tech. 59, 462–473.CrossRefGoogle Scholar
  2. 2.
    Antkowiak, T., Chase, R. (2003) Sensory innervation of the ovotestis in the snail Helix aspersa. J. Exp. Biol. 206, 3913–3921.CrossRefGoogle Scholar
  3. 3.
    Chase, R. (2000) Structure and function in the cerebral ganglion. Micro. Res. Tech. 49, 511–520.CrossRefGoogle Scholar
  4. 4.
    Chase, R. (2002) Behavior and its Neural Control in Gastropod Molluscs. Oxford University Press, New York.Google Scholar
  5. 5.
    Elo, J. E. (1938) Das Nervensystem von Lymnaea stagnalis (L.) Lam. Annales Zoologici (Helsinki) 6, 1–40.Google Scholar
  6. 6.
    Kerkut, G. A., Lambert, J. D. C., Gayton, R. J., Loker, J. E., Walker, R. J. (1975) Mapping of nerve cells in the sub-esophageal ganglia of Helix aspersa. Comp. Biochem. Physiol. 50A, 1–25.CrossRefGoogle Scholar
  7. 7.
    Pin, T., Gola, M. (1984) Axonal mapping of the neurosecretory Helix bursting cells. Functional aspects of peripheral multibranched axons. Comp. Biochem. Physiol. 79A, 611–620.CrossRefGoogle Scholar
  8. 8.
    Ram, J. L., Fong, P. P., Kyozuka, K. (1996) Serotonergic mechanisms mediating spawning and oocyte maturation in the zebra mussel, Dreissena polymorpha. Invert. Reprod. Develop. 30, 29–37.CrossRefGoogle Scholar
  9. 9.
    Schmalz, E. (1914) Zur Morphologie des Nervensystems von Helix pomatia L. Z. Wiss. Zool. 111, 506–568.Google Scholar
  10. 10.
    S.-Rózsa, K. (2002) Central representation of internal and external sensory information in the CNS of Helix pomatia L. and Lymnaea stagnalis L. Acta Biol. Hung. 53, 559–573.CrossRefGoogle Scholar
  11. 11.
    S.-Rózsa, K., Hernádi, L., Kemenes, Gy. (1986) Selective in vivo labelling of serotonergic neurons by 5,6-dihydroxytryptamine in the snail Helix pomatia L. Comp. Biochem. Physiol. 85C, 419–425Google Scholar

Copyright information

© Akadémiai Kiadó, Budapest 2004

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  • R. Chase
    • 1
    Email author
  • T. Antkowiak
    • 1
  • E. Geoffroy
    • 1
  • D. Weatherill
    • 1
  1. 1.Department of BiologyMcGill UniversityMontrealCanada

Personalised recommendations