大鼠耳蜗发育过程中突触素的表达差异

Differential Expression of Synaptophysin in the Developing Rat Cochlea

目的研究大鼠耳蜗发育过程中突触素(synaptophysin,SYN)的表达差异,探讨SYN表达与听觉功能发育成熟的关系及耳蜗中三磷酸腺苷(adenosine triphosphate,ATP)的来源。方法选取健康SD大鼠25只,按出生后天数将其分为出生后1、5、10、14、28天组(即:P1、P5、P10、P14和P28组),每组5只,运用免疫组化的方法比较各组大鼠耳蜗中SYN的表达差异。结果P1、P5和P10组大鼠顶回的Corti器、Kolliker器未发现SYN表达;P10组底回及蜗管中段、P14组和P28组Corti器的内、外螺旋束、Deiters细胞内侧缘有特异性表达;各组大鼠耳蜗螺旋神经元(spiral ganglion neuron,SGN)胞浆中均有SYN表达。结论大鼠耳蜗发育过程中SYN的表达存在差异,这种差异有利于神经末梢和靶细胞间构型建立,对听觉系统发育中形成正确的听觉信息编码可能起着关键作用。毛细胞、支持细胞中的ATP可能以非囊泡或以非SYN特异性染色的囊泡形式储存。

Objective To investigate the differential expression of synaptophysin（SYN） in the developing rat cochlea, to analyze the relationship between the expression of SYN and auditory functional development, and to explore the source of the adenosine triphosphate （ATP） in the cochlea. Methods The immunofluorescence was applied to observe the differential expression of SYN in the cochlea of SD rats on different days （p1, p5, p10, p14 and p28） after parturition. Results No significant stain was observed in the Kolliker organ or the Cord＇s organ of P1 , P5 and the top turn of the cochlea in P10. The SYN expression was turned on the outer spiral bundle ,the inner spiral bundle, and the medial wall of the Deiters＇ cell of the cochlea in P14,P28 and the second or the third turn of Corti＇s organ of P10. All the spiral ganglion neurons（SGN）were stained in different aged cochlea. Conclusion The expression of SYN was different during development of rat cochlea. This difference was in favor of the configuration constructed between nerve endings and target cells. It also played a key role in the formation of correct auditory coding during auditory system development. The hair cells and the supporting cells, possible the source of ATP in the cochlea,contained ATP that maybe existed in a non-vesicular form or specific staining of non SYN.