Vagal Afferent Projections from the Pharyngeal Jaw of the Cichlid Nile Tilapia Identified

Strategic Insights -

Researchers at Yokohama City University have made a significant discovery in the field of histochemistry. A study published in the European Journal of Histochemistry reveals that vagal innervation in the pharyngeal tooth and jawbones of Nile tilapia has been identified through macroscopic observations and immunohistochemistry. The research team, led by Kosuke Imura, Department of Neuroanatomy, Graduate School of Medicine, Yokohama City University, has provided new insights into the neural regulation of bone remodeling in the pharyngeal jaw.

Key Takeaways:

  • The study identified vagal innervation in the pharyngeal tooth and jawbones of Nile tilapia through macroscopic observations and immunohistochemistry.
  • The research revealed the apposition of the nerve and osteoclasts in the pharyngeal jaw, suggesting the possibility of neuronal regulation for bone remodeling.
  • The central projection from the vagal nerve, which innervates the pharyngeal jaws, remains unknown.
  • The study applied carbocyanine dye (DiI) into the vagus nerve, revealing DiI-labeled neurons in the caudal vagal ganglion.
  • The labeled fibers of the neurons were traced to the vagal lobe, revealing that they branched and ran dorsally before terminating in a band-like pattern.
  • The research concluded that pharyngeal tooth-derived sensory information might occur during occlusion and be processed precisely for determining the regurgitation and swallowing of prey.

Statistics:

  • The study focused on the pharyngeal jaw of the cichlid Nile tilapia (Oreochromis niloticus).
  • The research team, led by Kosuke Imura, consisted of five authors, including Imura, Akihito Takeda, Masato Endo, Masanori Nasu, and Kengo Funakoshi.
  • The study was published in the European Journal of Histochemistry in 2025, Volume 69, Issue 4.
  • The publication date for the journal article is 2025.
  • The article is freely available at https://doi-org.sdpl.idm.oclc.org/10.4081/ejh.2025.4248.

Sources:

  • NewsRx. Research from Yokohama City University Provides New Study Findings on Histochemistry [Vagal afferent projections from the pharyngeal jaw of the cichlid Nile tilapia (Oreochromis niloticus)]. Life Science Weekly. November 4, 2025; p 5244.
  • European Journal of Histochemistry. Vagal afferent projections from the pharyngeal jaw of the cichlid Nile tilapia (Oreochromis niloticus). 2025,69(4). (http://www.ejh.it/).