The Model And Analysis Of An Action Potential Propagated Along A Nerve Fiber

The nerve conduction velocity is one of the important and sensitive deliberatedindex of the nerve function, which is applied widely into the clinic diagnosis andfunction examination after healed of some neural disease. And it is also veryimportant for the basic research on nerve electrophysiology and the research onmovement medicine. Up to now, the experimental measure technology of the velocityof action potential propagated along nerve fibers, in which the typical method is thetwo spots measurement. Although this method is very simple, the error is great, andthe experimental method lacks of the theoretic basis. In the middle of 20 century, agreat lot of scholars simulated the relation between the velocity of action potentialpropagated along a myelinated fiber or an unmyelinated fiber and the fiber diameteror the temperature. The results were according to the experimental results. But by far,there are lacking in the quantitative analysis of the velocity of action potentialpropagated along a myelinated fiber and an unmyelinated fiber. In this paper, we first analyze the mechanism of action potential propagated alongan unmyelinated fiber, and present a hypothesis that the velocity of transmembranecurrent is the equivalent of the propagation velocity of action potential. Then usingthe H-H model and the cable equation we obtain the formula of the velocity. Insuccession, we apply a similar method to analyze the mechanism of action potentialpropagated along a myelinated fiber. Using the McNeal model and the CRRSS model,we obtain the formula of the velocity. In the end, we simulate the influence of eachmembrane parameter to the propagation velocity for myelinated fibers andunmyelinated fibers, respectively, which can enhance the usability of the twocomputational models.