Mathematical Distinction in Action Potential between Primo-Vessels and Smooth Muscle

Abstract

We studied the action potential of Primo-vessels in rats to determine the electrophysiological characteristics of these structures. We introduced a mathematical analysis method, a normalized Fourier transform that displays the sine and cosine components separately, to compare the action potentials of Primo-vessels with those for the smooth muscle. We found that Primo-vessels generated two types of action potential pulses that differed from those of smooth muscle: (1) Type I pulse had rapid depolarizing and repolarizing phases, and (2) Type II pulse had a rapid depolarizing phase and a gradually slowing repolarizing phase.

History of Bioelectrical Study and the Electrophysiology of the Primo Vascular System

“…In case of the excitable cell, the vascular smooth muscle like cell type [37], the intestinal smooth muscle like cell type [45] and the immune cell type are reported [46]. …”

“…He also observed the changing electrical potential by stimulation with various drugs, such as acetylcholine, modeled the electrical signals by BVP (Bonhoeffer-Van der Pol) modeling, and analyzed the findings by fractal theory. J. H. Choi, C. J. Choi, and Cho developed the electrophysiology of the primo vascular system after this research [43–45]. …”

“…The value of the potential was different from the action potential of a pacemaker of intestines. There were two types of cell groups reported as well [45]. …”

Review and Comment on the Relationship between Primo Vascular System and Meridians

“…Applying extracellular recording method, the researchers recorded two types of pulses generated by the primo vessels on the internal organ surface: type I pulses' feature was with fast depolarizing and repolarizing phases, and type II pulses' characteristic was with fast depolarizing phase and gradually slowing repolarizing phase. And moreover, basing on the sharp top and larger amplitude of the pulses induced by stimulating primo vessels, the researchers could distinguish them from the pulses generated by smooth muscle [57]. Using intracellular recording method, others found that the electrical potential rose slowly by an average of 10.5 ± 8.4 mV in 18.1 ± 14.0 seconds to a steady resting potential, and irregular bursts of spontaneously evoked spikes occurred in the resting potential with an average duration of 16.6 ± 14.9 seconds.…”

The Characteristics of Action Potentials in Primo Vessels and the Effects of Acetylcholine Injection to the Action Potentials

“…This result indicates that Primo-vessels have a distinct function from smooth muscles. However, it was difficult to determine what role Primo-vessels played because we only compared pulse shape to distinguish Primo-vessels and smooth muscles [9]. The action potentials from the different tissues have distinct pulse components, such as amplitude, duration, and frequency.…”