The Role of Connexin26 and Connexin30 in the Mouse Cochlea of Noise-Induced Hearing Loss.

Abstract

OBJECTIVE: We aimed to explore the role of connexin26 (Cx26) and connexin30 (Cx30) in the cochlea in noise-induced permanent threshold shifts (PTS) and temporary threshold shift (TTS). STUDY DESIGN: Prospective, controlled. SETTING: Laboratory. METHODS: A mouse model of noise-induced PTS and TTS was constructed. Western blots were used to detect the expression of Cx26 and Cx30 in the cochlea. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were used to assess the potential biological pathways. RESULTS: Both the expression of Cx26 and Cx30 showed a trend of first rising and then falling in noise-induced PTS. The expression of Cx26 increased greatly in the 24 hours noise exposure (P&#x2009;<&#x2009;.05) and reached the highest level in the 4&#x2009;hours after noise exposure (P&#x2009;<&#x2009;.05), then decreased gradually and returned to the control level on the seventh day after the noise exposure, when compared with the control group. The expression of Cx30 showed a similar trend in noise-induced PTS. However, both the expression of Cx26 and Cx30 showed a trend of first falling and then rising in noise induced TTS. The expression of Cx26/Cx30 reached its lowest level in the 4&#x2009;hours after noise exposure (P&#x2009;<&#x2009;.05), and then increased to the control level on the second day after noise exposure (P&#x2009;>&#x2009;.05), compared with the control group. The first KEGG and GO pathway may be related with oxidative phosphorylation. CONCLUSION: Cx26 and Cx30 may have an effect in noise induced PTS and TTS. Future studies are needed to confirm the results.