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

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.