Consequences of unilateral hearing loss: time dependent regulation of protein synthesis in auditory brainstem nuclei.
Conductive hearing impairment results in marked changes in neuronal activity in the central auditory system, particularly in young animals [Tucci, D.L., Cant, N.B., Durham, D., 1999. Conductive hearing loss results in a decrease in central auditory system activity in the young gerbil. Laryngoscope 109, 1359-1371]. To better understand the effects of conductive hearing loss (CHL) on cellular metabolism, incorporation of (3)H-leucine was used as a measure of protein synthesis in immature postnatal day 21 gerbils subjected to either unilateral CHL by malleus removal or profound sensorineural hearing loss by cochlear ablation. (3)H-leucine uptake was measured after survival times of 6 or 48h. Protein synthesis values were standardized to measurements from the abducens nucleus and compared with measurements from sham animals at similar age/survival times. Protein synthesis in the medial superior olive (MSO) was found to be significantly down-regulated (bilaterally) after CHL in animals surviving 48h. However, 6h after CHL manipulation, protein synthesis is up-regulated in MSO (bilaterally) and in the ipsilateral medial nucleus of the trapezoid body.
Hutson
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KA
Department of Surgery, Division of Otolaryngology-Head and Neck Surgery, Duke University Medical Center, Box 3805, Durham, NC 27710, USA.
Durham
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Tucci
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D000818:Animals; D001306:Auditory Pathways / Q000378:metabolism* / Q000473:pathology; D001933:Brain Stem / Q000378:metabolism* / Q000473:pathology; D017626:Cochlear Nucleus / Q000378:metabolism / Q000473:pathology; D015536:Down-Regulation; D005849:Gerbillinae; D006314:Hearing Loss, Conductive / Q000378:metabolism* / Q000473:pathology; D046088:Hearing Loss, Unilateral / Q000378:metabolism* / Q000473:pathology; D009419:Nerve Tissue Proteins / Q000096:biosynthesis*; D009847:Olivary Nucleus / Q000378:metabolism / Q000473:pathology; D013997:Time Factors; D015854:Up-Regulation
D009419:Nerve Tissue Proteins