TY - JOUR
T1 - Expression of ENaC in LPS-induced inflammation of middle ear mucosa
AU - Song, Jae Jun
AU - Kwon, Seong Keun
AU - Cho, Chang Gun
AU - Park, Seok Won
AU - Chae, Sung Won
N1 - Funding Information:
This study was supported by a grant from the Korea Healthcare Technology R&D Project, Ministry of Health & Welfare, Republic of Korea (A110416).
PY - 2012/11
Y1 - 2012/11
N2 - Conclusion: The expression of all three subunits of the epithelial sodium channel (ENaC) decreased after the lipopolysaccharide (LPS) injection and normalized as the fluid collection resolved. This implies that fluid collection in acute otitis media may be caused by the inhibition of ENaC function. Objectives: We investigated the expression levels of subunits of ENaC after an injection of LPS into the middle ear cavity of rats. Methods: Seventy-two Sprague-Dawley rats were assigned randomly into the five groups that received an LPS injection and the control group. A transtympanic injection of LPS (1 mg/ml) was done and rats were sacrificed 6, 12, 24, 72, and 120 h after the procedure. Real-time RT-PCR was carried out for ENaC-α, -β, -γ, and immunohistochemistry was performed for ENaC-α and -β. Results: The level of ENaC-α expression decreased 0.50-fold and 0.55-fold at 6 and 12 h, respectively (p < 0.05), but it normalized at 24 h. It increased 3.64-fold at 72 h and 3.24-fold at 120 h (p < 0.05). At 6 and 12 h after the LPS injection into the middle ear cavity, inflammation was induced and ENaC-α immunoreactivity decreased. At 24 h, ENaC-α immunoreactivity was normalized, then at 72 and 120 h after the injection it was increased.
AB - Conclusion: The expression of all three subunits of the epithelial sodium channel (ENaC) decreased after the lipopolysaccharide (LPS) injection and normalized as the fluid collection resolved. This implies that fluid collection in acute otitis media may be caused by the inhibition of ENaC function. Objectives: We investigated the expression levels of subunits of ENaC after an injection of LPS into the middle ear cavity of rats. Methods: Seventy-two Sprague-Dawley rats were assigned randomly into the five groups that received an LPS injection and the control group. A transtympanic injection of LPS (1 mg/ml) was done and rats were sacrificed 6, 12, 24, 72, and 120 h after the procedure. Real-time RT-PCR was carried out for ENaC-α, -β, -γ, and immunohistochemistry was performed for ENaC-α and -β. Results: The level of ENaC-α expression decreased 0.50-fold and 0.55-fold at 6 and 12 h, respectively (p < 0.05), but it normalized at 24 h. It increased 3.64-fold at 72 h and 3.24-fold at 120 h (p < 0.05). At 6 and 12 h after the LPS injection into the middle ear cavity, inflammation was induced and ENaC-α immunoreactivity decreased. At 24 h, ENaC-α immunoreactivity was normalized, then at 72 and 120 h after the injection it was increased.
KW - Epithelial sodium channel
KW - Inflammatory response
KW - Lipopolysaccharide
KW - Otitis media
UR - http://www.scopus.com/inward/record.url?scp=84867537055&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84867537055&partnerID=8YFLogxK
U2 - 10.3109/00016489.2012.697640
DO - 10.3109/00016489.2012.697640
M3 - Article
C2 - 22830999
AN - SCOPUS:84867537055
VL - 132
SP - 1145
EP - 1150
JO - Acta Oto-Laryngologica
JF - Acta Oto-Laryngologica
SN - 0001-6489
IS - 11
ER -