Acta Biologica Hungarica

, Volume 63, Supplement 2, pp 96–103 | Cite as

The 5-HT Immunoreactive Innervation of the Helix Procerebrum

  • Izabella Battonyai
  • K. ElekesEmail author


In the procerebrum of terrestrial snails, 5-HT is a key modulatory substance of the generation of synchronous oscillatory activity and odor learning capability. In this study, we have analyzed the characteristics of the 5-HT-immunoreactive (5-HT-IR) innervation of the distinct anatomical regions of the procerebrum of Helix pomatia, applying correlative light- and electron microscopic immunocytochemistry. A dense network of 5-HT-IR innervation was demonstrated in the cell body layer, meanwhile a varicose fiber system of different density occurred in the different neuropil regions. At the ultrastructural level, labeled varicosities were found to contact both procerebral cell bodies, and different unlabeled axon profiles in the neuropils. The labeled structures established mostly close non-specialized membrane contacts with the postsynaptic profiles. The overall dense distribution of 5-HT-IR innervation supports a general modulatory role of 5-HT in processing different olfactory events.


Procerebrum ultrastructure 5-HT immunocytochemistry Helix pomatia 


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© Akadémiai Kiadó, Budapest 2012

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (, 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

  1. 1.Balaton Limnological Institute, Department of Experimental ZoologyMTA Centre for Ecological ResearchTihanyHungary

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