神经生长锥内α-spectrin与F-actin的免疫细胞化学研究

IMMUNOCYTOCHEMICAL STUDY OF α-SPECTRIN AND F-ACTIN IN NERVE GROWTH CONES

目的 为了探讨α 血影蛋白 (α spectrin)和纤维型肌动蛋白 (F actin)在神经生长锥激烈运动与神经生长过程中的作用机制。方法 采用免疫双荧光染色法 ,以共聚焦激光扫描显微镜观察初代培养脊神经节细胞生长锥的连续水平断面上观察α spectrin和F actin的三维分布特点及其相互关系。结果 在水平面上 ,α spectrin和F actin分布在细胞质中 ,尤以细胞膜下、生长锥的P区伸展方向的前端和丝状伪足内分布最多 ,且α spectrin比F actin更接近细胞膜 ;在纵轴方向 ,α spectrin从基质侧到表面游离侧都有分布 ,而F actin在生长锥体部C区和表面游离侧分布较少。结论 提示α spec trin和F actin共同参与生长锥运动、神经生长外 ,还参与构筑生长锥内的三维网架及维持生长锥的极性。

Objective To study the mechanism of α-spectrin and F-actin in the movement and development changes of nerve growth cones. Method The three-dimensional distributionand relationship of α-spectrin and F-actin in nerve growth cones of the primary cultured chick embryo spinal ganglion cells were studied with confocal laser light micrsocope in horizontal continuous sections prepared with double immunofluorescent method. Result In the horizontal direction,α-spectrin and F-actin were distributed in the cytoplasm, mostly beneath the cell membrane, in the filopodia andin thehead of the stretching nerve growth cones; and α-spectrin was closer to the membrane than F-actin. In the longitudinal direction, they were distributed differently. F-actin was found less in the central part, the matrix side and the free surface side of the body of the nerve growth cones, while α-spectrin was found from the matrix side to the free surface side. Conclusion The resutlts suggest that both α-spectrin and F-actin participate in the movement and development of nerve growth cones .Besides, they take part in constructing the three-dimensionalnetwok and keeping polarity of the growth cones.