Application of TELC model to better elucidate neural stimulation by touch

Abstract

Aim: This study is to better understand how the transient ion transport activity of touch receptors could change the graded potential to stimulate an action potential firing.

Methods: The latest transmembrane-electrostatically localized protons/cations charges (TELC) theory is employed for numerical analysis to calculate the neural touch signal transduction responding time required to fire an action potential spike.

Results: A neural action potential spike was constructed successfully using newly developed time-dependent TELC-based neural transmembrane potential integral equations (Equations 5, 6, and 7). The results explicated that the TELC curve has an inverse relationship with neural transmembrane potential since its curve appears as an inverse mirror image to the action potential spike. Based on the TELC density at resting membrane potential of –70 mV calculated to be 3,900 (excess protons + cations) per μm² and that at the stimulation threshold level (–55 mV) calculated to be 3,100 (excess protons + cations) per μm² on extracellular membrane surface, the neural touch signal transduction responding time from PIEZO channel ion conduction to reduce the TELC density to the stimulation level of 3,100 TELC per μm² has now, for the first time, been calculated for action potential firing.

Conclusions: The activity of a single or a few PIEZO channels may be sufficient to generate a “graded potential” to trigger an action potential spike firing. With a high number (200–300) of PIEZO channels activated by touch, it can generate the required “graded potential” to reach the stimulation threshold level (–55 mV) within a neural touch signal transduction time as fast as 0.3 ms. The calculated neural touch signal transduction responding time (e.g., 0.3 ms) may have fundamental implications not only for neuroscience but also for other science and technology fields such as bioengineering and sports physiology.

Keywords

Neural stimulation by touch / neuronal touch responding time / transmembrane-electrostatically localized protons/cations / TELC capacitor / action potential / electrophysiology

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