镁离子对大鼠雪旺细胞增殖及NGF分泌的影响

Effect of magnesium on proliferation and NGF secretion in Schwann cells of rat

目的观察镁离子对体外培养大鼠雪旺细胞（Schwann cells,SCs）增殖及神经生长因子（nerve growth factor,NGF）分泌的影响。方法选取出生3～5 d SD大鼠,分离双侧坐骨神经行SCs体外培养,用S-100免疫细胞化学染色鉴定细胞纯度。取对数生长期SCs分别加入含不同浓度Mg Cl2（0、0.5、1、2 mmol/L）和10%FBS的DMEM培养基。分别于第2、4、6、8天,MTT法检测SCs增殖情况,ELISA法检测细胞分泌NGF水平。结果经双30 min差速贴壁法,可以去除大部分成纤维细胞。原代培养的SCs,接种24 h后即可贴壁生长。在培养的第72 h细胞胞体出现并肩平行排列的趋势,第7天可见细胞聚合。经免疫组织化学检测计数,培养6 d后的SCs,其纯度达到91%。各组SCs增殖活力均呈上升趋势（A组上升幅度最大,C组上升幅度最小）,各组分泌的NGF水平至第6天达峰值后均下降（A组上升幅度最大,C组上升幅度最小）,4组组间、不同时点间、组间·不同时点间交互作用差异有统计学意义（P〈0.05）。结论适宜浓度的Mg Cl2对体外培养大鼠SCs的增殖和分泌功能有促进作用。

Objective To investigate the effect of magnesium on proliferation and nerve growth factor（ NGF） secretion in Schwann cells（ SCs）. Methods 3 ～ 5 days old SD rats were used. The SCs were isolated from sciatic nerves in vitro. The positive cells were counted by using S- 100 immunocytochemical staining. SCs were divided into four groups. The culture medium was DMEM containing 10% FBS and different concentrations of Mg Cl2（ 0,0. 5,1,2 mmol/L）. MTT was used to detect the cell proliferation of the Schwann cells at 2,4,6,8 d.The expression of NGF was detected by ELISA. Results Most collagenoblast were removed by differential adhesion about 30 minutes. The primary-cultured SCs were adherent to the plastic surface of the cell culture dish and growed 24 h after inoculation. In the 72 th hour of cultivation,the cells showed the trend of parallel arrangement. In the 7th day,we could see cell aggregation under a microscope. Through counting by immunohistochemistry test,the purity of SCs reached 91% 6 days after cultivation. The purity of SCs was 91% by S-100 immunocytochemical staining. Compared with normal training group,0. 5 mmol / L Mg Cl2 group had a promoting effect on SCs proliferation and NGF secretion. There were significant differences in 4 groups,in different time points,and in the interaction of the groups vs time points（ P〈0. 05）. Conclusion Appropriate concentration of Mg Cl2 can stimulate the proliferation and NGF secretion of SCs of rat.