Expression of α,β,and γ subunits of epithelial sodium channel in the cochlea and endolymphatic sacof guinea pig
10.3760/cma.j.issn.1673-0860.2009.01.013
- VernacularTitle:豚鼠耳蜗和内淋巴囊上皮钠通道的表达
- Author:
Shi-Xun ZHONG
1
;
Zhao-Hua LIU
Author Information
1. 重庆医科大学附属第一医院
- Keywords:
Sodium channels;
Cochlea;
Endolymphatic sac;
Guinea pigs
- From:
Chinese Journal of Otorhinolaryngology Head and Neck Surgery
2009;44(1):49-52
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the distribution and role of α,βand γ subunits of epithelial sodium channel(ENaC) in the cochlea and endolymphatic sac of guinea pig. Methods The expression of α-, β- and γ-ENaC subunits proteins was studied by immunohistochemistry with the specific polyclonal rabbit antibodies against the α,β and γ subunits of rat ENaC. α-ENaC mRNA was detected by in situ hybridization with digoxin labeled cDNA probe. Results All three subunits of ENaC, α-, β- and γ-, were widely distributed in the labyrinth. In the cochlea, strong labeling of α-ENaC protein was found in the spiral limbns, and to a less extent, in the spiral ligament, organ of Corti and Reissner's membrane. The immunoreactivity of β-ENaC was observed in the spiral ligament, spiral limbus, spiral ganglion, organ of Corti and Reissner's membrane with a less intensity than that of α-ENaC. γ-ENaC was presented primarily in the superior part of the spiral ligament, spiral limbus, spiral ganglion, and weakly in the organ of Corti and Reissner's membrane. In the endolymphatic sac, intensive immunoreactivities of all three subunits were seen in the epithelial cells and the subepithelial cells at similar intensity, α-ENaC mRNA was localized in the spiral limbus, the inferior part of spiral ligament, stria vascularis, and epithelial cells and subepitbelial cells of endolymphatic sac. Conclusion Different subunits of the ENaC expressed in various cell regions of the cochlea and endolymphatic sac in distinct patterns may form the functional sodium channel to regulate the endolymph, thus serve to maintain homeostasis in inner ear.
