Normal Cochlear Function in mdx and mdxCv3 Duchenne Muscular Dystrophy Mouse Models

Objectives/Hypothesis: Sensorineural hearing loss has been found in association with inherited muscular dystrophies in humans and in mouse models. An increased brainstem auditory evoked response threshold has been previously reported in the dystrophin‐deficient mdx mouse model for Duchenne muscular...

Full description

Saved in:
Bibliographic Details
Published in:The Laryngoscope 1999-08, Vol.109 (8), p.1310-1312
Main Authors: Pillers, De-Ann M., Duncan, Nancy M., Dwinnell, Shannon J., Rash, Sean M., Kempton, J. Beth, Trune, Dennis R.
Format: Article
Language:English
Subjects:
Animal model
Biological and medical sciences
cochlea
Diseases of striated muscles. Neuromuscular diseases
dystrophin
Ear, auditive nerve, cochleovestibular tract, facial nerve: diseases, semeiology
hearing
Medical sciences
muscular dystrophy
Neurology
Non tumoral diseases
Otorhinolaryngology. Stomatology
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Objectives/Hypothesis: Sensorineural hearing loss has been found in association with inherited muscular dystrophies in humans and in mouse models. An increased brainstem auditory evoked response threshold has been previously reported in the dystrophin‐deficient mdx mouse model for Duchenne muscular dystrophy, suggesting that full‐length dystrophin (Dp427) is involved in hearing. The objective of the present study was to confirm cochlear dysfunction with this gene defect and determine whether the shorter carboxyl terminus isoforms of dystrophin are also critical in maintaining normal hearing. Study Design: Case controlled. Animal model. Methods: Auditory brainstem response (ABR) audiometry to pure tones was used to evaluate cochlear function. Fourteen mdx, 4 mdxCv3, and 13 age‐matched control (C57BL/6J and C57BL/10ScSn) male mice were tested at 5 weeks and 11 weeks of age. The ABR thresholds to tone‐burst stimuli at 4, 8, 16, and 32 kHz were obtained for each ear and statistically compared (ANOVA) for potential group differences. Results: Both mdx and mdxCv3 mice demonstrated normal ABR thresholds when compared with controls. Conclusions: Both mdx and mdxCv3 mouse models have normal hearing by ABR. The authors' data suggest that dystrophin and its carboxyl terminus isoforms do not play a critical role in hearing in the mouse. This was unexpected, as previous studies using the brainstem auditory evoked response method suggested that the mdx mouse has an increased threshold for hearing.
ISSN:0023-852X
1531-4995
DOI:10.1097/00005537-199908000-00023