活性氧对神经母细胞株SH-SY5Y细胞L型钙通道电流的影响

Effects of H_2O_2 on L-type calcium current in SH-SY5Y human neuroblastoma cells

目的 探讨氧自由基导致神经元钙超载的发生机制。方法 在神经母细胞株 SH- SY5 Y细胞体外培养的基础上 ,采用全细胞膜片钳技术 ,观察 H2 O2 对 SH- SY5 Y细胞 L 型钙电流 (ICa,L)的影响。结果 (1) H2 O2 能够明显增加峰值 ICa,L,且该作用具有浓度依赖性。 (2 ) H2 O2 使 ICa,L的 I- V相关曲线下移 ,但对其形状和最大激活电位无明显影响。结论 H2 O2 对 L 型钙通道有明显的增强作用 ,此可能是其导致神经元钙超载的机制之一。

Objective To study the mechanisms of Ca 2+ overload in neurons induced by oxygen free radical.Methods L type calcium channel currents were recorded from human neuroblastoma cells, SH SY5Y line, using whole cell patch clamp techniwues.Results H 2O 2 were shown to increses L type calcium channel currents(Ica, L),concentration dependently and to shife the I V curves of Ica, L downwardly.Conclusion H 2O 2 activated significantly L type calcium channel in SH SY5Y human neuroblastoma cells, it might be one of the mechanisims of Ca 2+ overload in neurons induced by oxygen free radical.