白介素1β对大鼠皮层神经元钠电流的急性作用

Acute effects of IL-1β on sodium current in cortical neurons of rats

白介素1β(Interleukin-1β,IL-1β)是重要的促炎细胞因子,在多种中枢神经系统的损伤和疾病过程中发挥关键作用。电压门控的钠通道是神经元中最重要的离子通道之一,是产生再生性动作电位的基础,决定了神经元的兴奋性等电学性质,也与多种中枢疾病过程相关。然而,现在还没有直接关于IL-1β与中枢钠通道的相互关系的研究。在该研究中,使用全细胞膜片钳记录测定了IL-1β对培养的皮层神经元钠电流的急性作用,并分析了由此对动作电位的影响。结果显示,IL-1β对钠电流幅度只有较小的抑制,而显著降低钠通道的半激活电压,不改变激活的斜率因子和失活性质,这个作用引起动作电位阈值显著降低。这些结果提示在损伤和疾病过程中,快速释放的IL-1β可能会增加神经元兴奋性,从而恶化神经损伤过程。

Interleukin-1β（IL-1β） is an important proinflammatory cytokine that plays a key role in injuries and diseases of the central nervous system（CNS）.The voltage-gated Na＋ channel is the most important ion channel of neurons,and is essential for regenerative action potential（AP）.The Na＋ channel also contributes to many diseases of the brain.However,relations between IL-1β and central Na＋ channels remain unreported.In this study,whole cell patch-clamp recording was used to investigate the acute effects of IL-1β（10 ng/mL） on voltage-dependent Na＋ currents and AP of cultured cortical neurons from rats.Results showed that the half-activation voltage of Na＋ channels and the threshold of AP,but not the amplitude,slope factor of activation,and inactivation properties,were affected by IL-1β.These data suggest that increased IL-1β in injury and disease may upregulate the excitability of neurons,and thereby exacerbate neurotoxicity.