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.
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.
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References
Batty HK, Millhouse OE (1976a) Ultrastructure of the Gunn rat substantia nigra. I. Cytoplasmic changes. Acta Neuropathol (Berl) 35:93–107
Batty HK, Millhouse EE (1976b) Ultrastructure of the Gunn rat substantia nigra. II. Mitochondrial changes. Acta Neuropathol (Berl) 34:7–19
Belal A Jr (1975) Effect of hyperbilirubinemia on the inner ear in Gunn rats. J Laryngol Otol 89:259–265
Blanc WA, Johnson L (1959) Studies on kernicterus. J Neuropathol Exp Neurol 18: 165–189
Chisin R, Perlman M, Sohmer H (1979) Cochlear and brain stem responses in hearing loss following neonatal hyperbilirubinemia. Ann Otol Rhinol Laryngol 89:352–357
Greenfield S, Majumdar APN (1974) Bilirubin encephalophathy: Effect on protein synthesis in the brain of the Gunn rat. J Neurol Sci 22: 83–89
Gunn CK (1938) Hereditary acholuric jaundice in a new mutant strain of rats. J Hered 29:137–139
Jew JY, Williams TH (1977) Ultrastructural aspects of bilirubin encephalopathy in cochlear nuclei of the Gunn rat. J Anat 124:599–614
Jew JY, Sandquist D (1979) CNS changes in hyperbilirubinemia — functional implications. Arch Neurol 36:149–154
Jewett DL, Romano MN (1972) Neonatal development of auditory system potentials averaged from the scalp of rat and cat. Brain Res 36: 101–115
Johnson L, Sarmiento F, Blanc WA, Day R (1959) Kernicterus in rats with an inherited deficiency of glycuronyl transferase. AMA J Dis Child 97:591–608
Kaga K, Kitazumi E, Dodama K (1979) Auditory brain stem responses of kernicterus infants. Int J Ped ORL 1: 264
Lathe GH, Walker M (1958) The synthesis of bilirubin glucuronide in animal and human liver. Biochem J 70: 705–712
Schutta HE, Johnson L (1969) Clinical signs and morphologic abnormalities in Gunn rats treated with sulfadimethoxine. J Pediatr 75:1070–1079
Schutta HE, Johnson L, Neville HE (1970) Mitochondrial abnormalities in bilirubin encephalopathy. J Neurophatol Exp Neurol 29:296–305
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Levi, G., Sohmer, H. & Kapitulnik, J. Auditory nerve and brain stem responses in homozygous jaundiced gunn rats. Arch Otorhinolaryngol 232, 139–143 (1981). https://doi.org/10.1007/BF00505033
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DOI: https://doi.org/10.1007/BF00505033