豚鼠耳蜗一氧化氮合酶异型体的定位

目的研究一氧化氮合酶(NOS)的异型体在豚鼠耳蜗的定位分布,以探讨一氧化氮(NO)在内耳听觉生理和病理生理机制中的作用。方法使用特异性NOS异型体抗体,采用ABC免疫组化染色法,观察NOS异型体在正常豚鼠耳蜗的定位表达。结果NOS Ⅰ主要分布在内骨膜、螺旋神经节的核周体、螺旋韧带和Corti's器的细胞。NOSⅢ是耳蜗的主要NOS异型体免疫染色,其主要免疫染色分布于耳蜗神经、螺旋神经节核周体、螺旋韧带和耳蜗毛细血管球的内皮细胞,也见于Corti's器的细胞和神经纤维。NOS Ⅱ在正常豚鼠耳蜗内不表达。 结论结构型NOS(cNOS)表达在耳蜗的多个部位,表明NO参与内耳的正常生理功能,包括神经突触的神经传导、耳蜗血流的调节和耳蜗的骨代谢。

Expression of nitric oxide synthase isoforms in cochlea of guinea pig

Objective The distribution of nitric oxide synthase (NOS) isoforms was investigated in the cochlea of the guinea pig by immunohisto-chemistry. Methods The expression of NOS isoforms in the cochlea of the guinea pig was examined with isoform selective anti-NOS antibodies by the avidin-biotin-complex (ABC) procedure. Results Type NOS 1 mainly distributed in the endosteum, the perikaryia of the spiral ganglion cells, the cells of Corti's organ and the spiral ligament in the guinea pig cochlea. Type NOS El mainly distributed in the cochlear nerve, perikaryia of the spiral ganglion cells and the spiral ligament, and also in the cells and the nerve fibre of Corti's organ and in the endothelial lining of cochlear glomeruli. Immunostainning for Type NOS II revealed no immunoreactivity. Conclusion Expression of cNOS isoforms ( Type NOS 1 and Type NOS III) in cochlea are detected. It suggests that NOS involves in the cochlear physiology including the synaptic neurotransmition in cochlea, the regulation of microcirculation and the bone metabolism in the cochlea.