不同发育阶段人胚胎脊髓中细胞凋亡的表达及变化

摘要

Objective:To explore the regularity of cell apoptosis in the development of the human embryonic spinal cord. Methods:The cell apoptosis in the human embryonic spinal cord in different stages ( from 3 weeks to 8 months) was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNED method. Results: TUNEL-posi-tive cells in neuroepithelium could be found throughout the development of the spinal cord and peaked at 5 weeks. TUNEL-positive cells in basal plate and alar plate could be detected as 5 weeks and 6 weeks. The number of TUNEL-positive cells in the basal plate and alar plate peaked at 6 weeks and 11 weeks. TUNEL-positive cells in marginal layer showed up at 9 weeks and peaked at 5 months, then decreased gradually. Conclusion: The appearance and peak time of the cell apoptosis in the human embryonic spinal cord are different in distinct embryonic age. It indicates that the apoptosis in different parts of the spinal cord is not synchronous.%目的:研究人胚胎脊髓生长发育过程中细胞凋亡的变化趋势.方法:采用TUNEL法标记检测从3周至8个月不同胚胎龄段脊髓细胞凋亡的变化规律.结果:3周在神经管上皮即可见到密集的凋亡细胞,5、6周基板、翼板形成后即可在其内见到凋亡细胞,而边缘层内的凋亡细胞出现时间较其他部位晚,9周才可见到,中央管神经上皮的凋亡细胞高峰出现时间较早,5～6周达高峰,3个月后趋于稳定,而腹角内凋亡细胞高峰出现时间在6周,背角内凋亡细胞高峰出现时间为11周,其后随着脊髓的发育,凋亡逐渐减少.结论:脊髓不同部位细胞凋亡出现时间和达到高峰的时间均不同,提示在脊髓的不同部位凋亡并不同步.