Gentamicin affects connexin 26 expression in the cochlear lateral wall.
OBJECTIVE
Aminoglycosides may decrease the expression of some proteins participating in ion-exchange in the cochlear lateral wall. Connexin 26 expression in the lateral wall may play a role in acquired hearing loss by maintaining the endocochlear potential and potassium concentration in the endolymph. We examined the effects of gentamicin on the expression of connexin 26 to obtain a better understanding of aminoglycoside ototoxicity.


METHODS
We detected changes in connexin 26 protein and mRNA expression in the cochlear lateral wall using immunohistochemistry staining, western blotting, and real-time PCR in rats after administration of a single dose of gentamicin.


RESULTS
The expression of connexin 26 increased over time in type III fibrocytes after gentamicin administration. Elevated protein levels were detected 3 h after the single injection of gentamicin; while, mRNA levels increased after 24 h.


CONCLUSIONS
Connexin 26 plays an important role in the acute effects of high-dose gentamicin and is probably involved in the pathogenesis of ototoxic deafness.
Institute of Otology, Department of Otolaryngology and Head and Neck surgery, Second Xiangya Hospital, Central South University, Changsha 410011, China.
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Hu
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Lai
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Xie
D000818:Animals; D003051:Cochlea / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D004195:Disease Models, Animal; D005839:Gentamicins / Q000494:pharmacology*; D034381:Hearing Loss / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D007274:Injections, Intraperitoneal; D008297:Male; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D017630:Connexins; D005839:Gentamicins; C000607044:Gjb2 protein, rat; D011500:Protein Synthesis Inhibitors; D012333:RNA, Messenger; D000072259:Connexin 26