The nitric oxide/cyclic GMP pathway in the olfactory processing system of the terrestrial slug Limax marginatus

Sayoko Fujie, Hitoshi Aonuma, Iori Ito, Alan Gelperin, Etsuro Ito

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32 Citations (Scopus)


To examine the distribution of nitric oxide (NO)-generative cells and NO-responsive cells in the tentacles and procerebral lobes (olfactory processing center) of terrestrial slugs, we applied NADPH diaphorase (NADPH-d) histochemistry and NO-induced cyclic GMP (cGMP)-like immunohistochemistry. We found that NADPH-d reactive cells/fibers and cGMP-like immunoreactive cells/fibers were different, but they were localized adjacent to each other, in both the tentacles and the procerebral lobes. Then, we measured the concentration of NO that was generated around the procerebral lobes using an NO sensitive electrode, when the olfactory nerve was electrically stimulated as a replacement for an odorant stimulus. Stimulation of the olfactory nerve evoked an increase in NO concentration at nanomolar levels, suggesting that binding of nanomolar concentrations of NO to the prosthetic heme group activates soluble guanylyl cyclase. Taken together with previously reported physiological data, our results, therefore, showed that the NO/cGMP pathways are involved in slug olfactory processing.

Original languageEnglish
Pages (from-to)15-26
Number of pages12
JournalZoological Science
Issue number1
Publication statusPublished - 2002 Aug 26



  • Gaseous signaling molecule
  • Mollusk
  • NADPH-diaphorase histochemistury
  • NO measurement
  • Procerebral lobe

ASJC Scopus subject areas

  • Animal Science and Zoology

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