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Archives of oto-rhino-laryngology

, Volume 232, Issue 2, pp 139–143 | Cite as

Auditory nerve and brain stem responses in homozygous jaundiced gunn rats

  • G. Levi
  • H. Sohmer
  • J. Kapitulnik
Article

Summary

In humans, functional evidence based on recording cochlear microphonic, auditory nerve, and brain stem responses has shown that the site of lesion in hearing loss following neonatal hyperbilirubinemia is the auditory nerve (with sparing of the hair cells). Structural damage to the central nervous system (CNS) including the cochlear nuclei has been demonstrated in adult, homozygous Gunn rats which develop hyperbilirubinemia shortly after birth. In an attempt to use the Gunn rat as an experimental model for bilirubin-induced CNS damage, auditory nerve and brain stem responses (ABR) were recorded in jaundiced (homozygous) and non-jaundiced (heterozygous) Gunn rats and in Sabra (Wistar) rats. All of the rats including the jaundiced Gunn rats had normal ABR and responded behaviorally to sound stimuli. These results suggest that the adult jaundiced Gunn rat retains auditory function and in this way differs from human patients in whom neonatal jaundice has lead to hearing loss. Therefore, the adult homozygous Gunn rat probably cannot serve as a model for hearing loss due to hyperbilirubinemia.

Key words

Auditory nerve Brain stem Gunn rats Jaundice Hyperbilirubinemia Cochlear microphonic 

Die Antwort von Hörnerv und Hirnstamm bei ikterischen Ratten

Zusammenfassung

Der Versuch, Ratten als experimentelles Modell eines durch Bilirubin verursachten Schadens im ZNS einzusetzen, zeigte, daß bei allen Ratten mit Gelbsucht normale Reaktionen des Hörnervs und des Hirnstamms auf akustische Reize zu registrieren waren. Da sich so die Reaktionen auf akustische Stimuli bei erwachsenen Ratten mit Gelbsucht von denen beim Menschen mit Ikterus neonatorum unterscheiden, sind Ratten nicht als Modell zur Untersuchung einer durch Hyperbilirubinämie verursachten Hörstörung geeignet.

Schlüsselwörter

Hörnerv Hirnstamm Ratte Gelbsucht Hyperbilirubinämie Cochlea-Mikrophonpotentiale 

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References

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Copyright information

© Springer-Verlag 1981

Authors and Affiliations

  • G. Levi
    • 1
  • H. Sohmer
    • 1
  • J. Kapitulnik
    • 2
  1. 1.Department of PhysiologyHebrew University-Hadassah Medical SchoolJerusalemIsrael
  2. 2.Department of PharmacologyHebrew University-Hadassah Medical SchoolJerusalemIsrael

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