Immunohistological Studies on the Distribution of Learning-Related Peptides in the Central Nervous System of Conditioned Lymnaea


Behavioral conditioning in Lymnaea increased the amount of immunolabeling in the central nervous system for the memory-associated protein calexcitin. The staining level of anti-calexcitin positive neurons was always stronger in conditioned animals than in naïve animals. In the visuo-vestibular conditioned animals, right-parietal and visceral group neurons as well as withdrawal-related neurons were positively stained with anti-calexcitin antibody. In taste-aversion conditioned animals, right-parietal visceral G-group neurons and withdrawal-related neurons were selectively stained. These neurons are candidate neurons for modulation by these conditioning paradigms.


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Correspondence to M. Sakakibara.

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Nomura, Y., Hatakeyama, D., Horikoshi, T. et al. Immunohistological Studies on the Distribution of Learning-Related Peptides in the Central Nervous System of Conditioned Lymnaea. BIOLOGIA FUTURA 59, 81–92 (2008).

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  • Calexcitin
  • visuo-vestibular conditioning
  • taste-aversion conditioning
  • immunohistochemistry
  • whole-body withdrawal response