Zhang Xu, Roppolo James, de Groat William, Tai Changfeng
Capital University of Medical Sciences, Beijing 100054, P.R.China; Department of Pharmacology, University of Pittsburgh, Pittsburgh, PA 15261,USA; E-mail:
Conf Proc IEEE Eng Med Biol Soc. 2005;2005:4247-50. doi: 10.1109/IEMBS.2005.1615402.
Nerve conduction block induced by high frequency biphasic electrical current was simulated using a lumped circuit model of the myelinated axon based on Frankenhaueuser-Huxley (FH) equations. Axons of different diameters (5-20 μm) can be blocked completed when the stimulation frequency is above 10 kHz. At higher frequency a higher stimulation intensity is needed to block nerve conduction. Larger diameter axons have lower block threshold. The activation of potassium channels, rather than inactivation of sodium channels, is the possible mechanism underlying the nerve conduction block of the myelinated axon induced by high frequency biphasic pulse current. This simulation study, which provides more information about the axonal conduction block induced by high frequency biphasic pulse current, can guide future animal experiments as well as optimize stimulation waveforms for electrical nerve block in possible clinical applications.
基于弗兰克豪泽-赫胥黎(FH)方程,使用有髓神经纤维的集总电路模型模拟了高频双相电流诱导的神经传导阻滞。当刺激频率高于10kHz时,不同直径(5-20μm)的轴突可被完全阻滞。在更高频率下,需要更高的刺激强度来阻断神经传导。直径较大的轴突具有较低的阻滞阈值。钾通道的激活而非钠通道的失活,可能是高频双相脉冲电流诱导有髓神经纤维神经传导阻滞的潜在机制。该模拟研究提供了更多关于高频双相脉冲电流诱导的轴突传导阻滞的信息,可指导未来的动物实验,并在可能的临床应用中优化电神经阻滞的刺激波形。