大鼠颅底软骨联合细胞凋亡信号传导途径的研究

Study on apoptosis signal transduction pathways of cranial base synchondrosis cell in rats

目的研究大鼠生长发育过程中颅底细胞的凋亡活动,探讨软骨联合细胞凋亡途径相关信号因子iNOS、Fas的表达及分布规律。方法选用出生后4、8、16、32、48、64、128 d的SD大鼠的颅底软骨联合组织。通过末端脱氧核苷酸转移酶介导的缺口末端标记法(TUNEL),iNOS及Fas的免疫组化法来检测颅底软骨联合细胞凋亡途径的时空特征,和各途径之间的相关性。结果各期标本均可见黄色荧光TUNEL凋亡软骨细胞,出生后4、8 d大鼠软骨联合的肥大区、交界区发现少量细胞凋亡现象;随时间推移细胞凋亡主要出现在肥大区、交界区和两侧的骨小梁,且细胞数逐渐增多。iNOS主要在出生后4、8、16 d的大鼠颅底软骨联合中间静止区、增殖区表达。Fas则存在于几乎各个时期的软骨联合各层,以肥大区、交界区表达为多。结论颅底软骨联合的生长发育与软骨细胞凋亡密切相关并存在Fas和NO两种凋亡途径。Fas途径发挥主要作用,NO途径对静止区和增殖区的生长意义更大。

A Objective To study the apoptosis activity of the basal cells during the growth and development of rats,and iNOS,Fasex pression and the regularities of distributionin this process. Methods SPF grade SD male rats were divided into seven groups （4,8,16, 32,48,64,128d）. TUNEL method and immunohistoehemical S-ABC method were used to detect temporal and spatial characteristics of the apoptotic pathways and correlation between each way. Results Yellow fluorescent TUNEL cartilage cell apoptosis can be seen in each group. 4d,8d, 16d after birth, a small amount of cell apoptosis appeared in the hypertrophic zone and the junctional zone of the synehondrosis and the number of cells increased as the time went by. iNOS mainly expressed in the quiescent zone and the proliferative zone. Fas existed in almost every period of each layer of cartilage joint and expressed more in the hypertrophic zone and the junctional zone. Conclusions The growth and development of synehondrosis is closely linked with ehondrocyte apoptosis. There were two path ways in the synchondrosis. Fas pathway plays a leading role while mitochondrion pathway is more significant to the growth in quiescent zone and proliferative zone.