小鼠耳蜗核因子-κB p50免疫组化定位

目的 了解核因子-κB(NF-κB)在耳蜗的表达情况.方法 小鼠皮下注射卡那霉素(KA),鼓室注射脂多糖(LPS),以注射等量生理盐水作为对照,用多克隆兔抗体NF-κB p50免疫组化染色,观察NF-κB p50在小鼠耳蜗的表达.结果 NF-κB p50主要定位在耳蜗的螺旋缘、盖膜、血管纹、螺旋韧带、螺旋神经节和神经纤维.整个耳蜗各圈均可观察到免疫反应,而螺旋韧带、盖膜、螺旋突、螺旋神经节和神经纤维均可观察到较强的免疫反应,Corti器的免疫反应比上述结构要弱一些.Corti器的内、外毛细胞,内、外柱细胞,Deiter细胞和Claudious细胞均可观察到NF-κB p50的免疫反应,这些免疫反应在内沟细胞、Hensen细胞和Claudious细胞较弱,而在螺旋神经节可观察到较强的免疫反应,内、外毛细胞核未见免疫反应.结论 注射脂多糖和卡那霉素可使NF-κB p50在小鼠耳蜗产生急性反应.

Immunohistochemical localization for nuclear factor kappa B p50 in cochlea of mice

Objective To show the capability of NF-κB expression in cochlea. Methods Kanamycin (KA) was subcutaneously injected twice daily for 3 and 7 days with an eight hours interval between two injections, and lipopolysaccharide (LPS) was injected into the tympanic cavity of mice. Equal amount of saline was injected for 7 days as control. Frozen sections of all mice cochleae were examined immmunohistochemichally with rabbit polyclonal NF-κB p50. Expression of NF-κB p50 immunoreactivity of mouse cochleae is identified as showed as brown reaction products characteristic of DAB immunohistochemistry. Results Immnoreactivity NF-κB p50 in mouse cochlea was localized in the organ of Corti, spiral limbus, tectorial membrane, the vascular stria, spiral ligament, spiral ganglion and nerve fibers. The immunoreaction could be observed in all spirals throughout the cochlea. Stronger staining was visible in spiral ligament, tectorial membrane, spiral prominence, spiral ganglion and nerve fibers, and the organ of Corti. The immunoreaction in the vascular stria was weaker than that in the structures mentioned above. The immunoreaction in the organ of Corti was observed in inner hair cells (IHC) and outer hair cells (OHC), inner and outer pillar cells, Deiter's cells, and Boettcher's cells. The immunoreaction was weaker in inner sulcus cells, Hensen's cells and Claudius'cells. The stronger immunoreaction was observed in nucleus of spiral ganglion cells. The nucleus of IHC and OHC remained unstained. Conclusion The injection of LPS/KA can promote NF-κB p50 expression to induce an acute reaction in mouse cochlea.