title: The peripheral processes of spiral ganglion cells after intracochlear application of brain-derived neurotrophic factor in deafened guinea pigs.
abstract: OBJECTIVE
  To characterize the effects of deafening and subsequent treatment with brain-derived neurotrophic factor (BDNF) on the peripheral processes (PPs) of spiral ganglion cells (SGCs) in guinea pigs.
  
  
  BACKGROUND
  BDNF may prevent degeneration of neural structures after loss of hair cells with possible relevance for cochlear implant candidates.
  
  
  METHODS
  Guinea pigs were deafened with a combination of kanamycin and furosemide. Two weeks after deafening, intracochlear BDNF treatment was started with osmotic pumps for 4 weeks. Two weeks after cessation of BDNF treatment, the cochleae were analyzed. PPs were counted and morphologically characterized with respect to myelination, size, and shape.
  
  
  RESULTS
  Deafening reduced the number of PPs. We found that BDNF treatment, started 2 weeks after deafening, significantly reduced this degenerative effect. The remaining processes showed an altered morphology; compared with normal, the size was reduced in deafened untreated animals and increased in BDNF-treated animals. The myelin sheath seemed thinner in BDNF-treated animals.
  
  
  CONCLUSIONS
  We conclude that BDNF has potential as an agent that can improve the interface between cochlear implants and the auditory periphery.
authors: Department of Otorhinolaryngology-Head and Neck Surgery, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands.
authors: Laurien
authors: L
authors: Waaijer
authors: Sjaak F L
authors: SF
authors: Klis
authors: Dyan
authors: D
authors: Ramekers
authors: Martinus H W
authors: MH
authors: Van Deurzen
authors: Ferry G J
authors: FG
authors: Hendriksen
authors: Wilko
authors: W
authors: Grolman
mesh_terms: D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology*; D003638:Deafness / Q000139:chemically induced / Q000473:pathology*; D005665:Furosemide; D006168:Guinea Pigs; D006198:Hair Cells, Auditory / Q000187:drug effects* / Q000473:pathology; D007612:Kanamycin; D009186:Myelin Sheath / Q000187:drug effects / Q000473:pathology; D009410:Nerve Degeneration / Q000473:pathology*; D009474:Neurons / Q000187:drug effects / Q000473:pathology; D013136:Spiral Ganglion / Q000187:drug effects* / Q000473:pathology
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D007612:Kanamycin; D005665:Furosemide