摘要
目的 研究大鼠出生后发育时螺旋神经节 (spiralganglion ,SG)神经元凋亡和分化的关系。方法 应用透射电镜观察 1、3、5、7、10、14和 30天龄大鼠螺旋神经节神经元超微结构的变化及细胞凋亡现象。结果 大鼠出生后 5和 7天 ,在透射电镜下观察到SG神经元凋亡 ,其典型的超微结构改变为染色质凝聚和着边形成的新月样结构、凋亡小体和细胞皱缩 ;随后的发育阶段细胞凋亡现象消失 ;最早可识别的富含神经丝的Ⅱ型神经元 (neuron2 ,N2 )出现在出生后 7天 ,新出现的N2 有明显的细胞皱缩现象 ;在随后发育的各阶段 ,SG中Ⅰ型神经元 (neuron1,N1)和N2 的结构特征更明显 ,逐渐发育成熟。结论 神经元凋亡是大鼠螺旋神经节出生后发育过程中的一个重要事件 ,发生在N2 分化过程中 ,可能与SG中N2
Objective To study cell apoptosis and differentiation in postnatal developing spiral ganglion(SG)of rat.Methods By means of transmission electron microscope(TEM),cell apoptosis and the ultrastructure of rat SG neurons were investigated during postnatal days 1,3,5,7,10,14,and 30.Results In P5 and P7,neural cell apoptosis was observed in rat SG neuron.The typical morphological alterations of apoptotic cells included a crescent-shaped band of condensed chromation round the nuclear periphery,apoptotic bodies,and cell shrinkage.The first appeared type 2 neurons with densely packed neurofilaments in the cytoplasm could be recognized with confidence at postnatal day 7.The type 2 neurons at this time showed obvious signs of cell shrinkage.Cell apoptosis disappeared subsequently.In subsequent developing period,the morphological characteristics of type 1 and type 2 neurons became more remarkable and gradually achieved their mature structure.Conclusion The neural cell apoptosis was an important event in the postnatal development of rat SGCS.Cell apoptosis,occurred prior to appearance of the type 2 neurons,may be related to remodeling of the outer hair cell innervation and type 2 neuron differentiation.
出处
《听力学及言语疾病杂志》
CAS
CSCD
2002年第3期183-184,T002,共3页
Journal of Audiology and Speech Pathology
