PTX阻断溶血磷脂酸对大鼠胚胎神经干细胞的促增殖作用

目的 观察溶血磷脂酸(lysophosphtidic acid,LPA)对大鼠胚胎神经干细胞(neural stem cells,NSCs)的增殖的影响以及百日咳毒素(pertussis toxin,PTX)对LPA作用的影响.方法 体外培养神经干细胞,对生成的神经干细胞球进行计数显示增殖情况.结果 ①在特殊的无血清培养液中加入低浓度LPA(0.01-1.0μmol/L)后,神经干细胞球数量呈剂量依赖性增加,表明LPA对NSCs有显著的促增殖作用;②培养液中同时加入LPA和PTX后,神经干细胞球计数显示LPA引起的NSCs的增殖被抑制了98%.结论 PTX阻断了LPA对大鼠胚胎神经干细胞的促增殖作用,从而推测LPA的促增殖作用可能主要通过PTX敏感的Gi-Ras-Raf-MAPK信号转导途径实现.

PTX blocks the promotive action of LPA on proliferation of embryonic neural stem cells in rats

Objective To study the effect of lysophosphatidic acid(LPA)on the proliferation of rat embryonic neural stem cells (NSCs) in vitro and the effect of pertussis toxin (PTX) on LPA-induced promotive proliferation of NSCs. Methods NSCs were cultured in vitro, and neurospheres were counted.Results ① Lower concentrations of LPA (0.01-1.0 μmol/L) dose-dependently increased the numbers of neurospheres cultured in specific serum-free media, which indicated a significant promotive action of LPA on the proliferation of NSCs. ② After NSCs were treated by 1.0 μmol/L LPA combined with PTX, 98% of the LPA-induced proliferation was blocked. Conclusion These results suggest that the promotive effect LPA might be brought about mainly by the PTX-sensitive Gi-Ras-Raf-MAPK pathway rather than the PTX-insensitive ones.