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Updated: Jul 26, 2026

Selective Tracing of Auditory Fibers in the Avian Embryonic Vestibulocochlear Nerve
11:27

Selective Tracing of Auditory Fibers in the Avian Embryonic Vestibulocochlear Nerve

Published on: March 18, 2013

Developing inner ear sensory neurons require TrkB and TrkC receptors for innervation of their peripheral targets

T Schimmang1, L Minichiello, E Vazquez

  • 1Departamento Bioquimica, Biologia Molecular y Fisiologia, Facultad de Medicina, Universidad de Valladolid, CSIC, Spain.

Development (Cambridge, England)
|October 1, 1995
PubMed

Insights

The study reveals that TrkB and TrkC receptors are crucial for maintaining nerve connections in the inner ear. Genetic mutations affecting these receptors lead to significant neuronal loss and innervation defects in the auditory and vestibular systems.

Area of Science:

  • Neuroscience
  • Developmental Biology
  • Genetics

Background:

  • The trkB and trkC genes are vital during the development of the auditory and vestibular systems.
  • Understanding the function of these genes is key to explaining inner ear formation.

Purpose of the Study:

  • To investigate the roles of trkB and trkC in the development of the auditory and vestibular systems.
  • To analyze the impact of mutations in the tyrosine kinase catalytic domain of trkB and trkC.

Main Methods:

  • Neuroanatomical analysis of mice with germline mutations in trkB and trkC genes.
  • Comparative analysis of vestibular and cochlear ganglia in homozygous mutant mice.
  • Developmental studies tracking fiber innervation and degeneration.

Main Results:

  • trkB mutations caused severe reduction in vestibular neurons and cochlear neurons innervating outer hair cells, with innervation defects.
  • trkC mutations led to moderate vestibular neuron reduction and loss of cochlear neurons innervating inner hair cells.
  • Developmental studies showed initial innervation followed by degeneration, indicating a role in neuronal survival and maintenance.

Conclusions:

  • TrkB and TrkC receptors are essential for the survival of specific neuronal populations in the inner ear.
  • These receptors play a critical role in maintaining target innervation within the peripheral sensory system.
  • Defects in TrkB and TrkC signaling result in significant auditory and vestibular system abnormalities.

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