Phase Depolarizations Action Potential

The depolarization phase of the action potential is a period that covers the period of time from the end of restoration of membrane permeability after a series of action potentials until the end of membrane depolarization. The restoration of permeability after the rapid repolarization phase determines the resting potential of the nerve fiber. The resting potential is the constancy of the distribution of charges inside and outside the cell, which determines the complete immunity of the cell to the effects of external stimuli.

Depolarization is a change in cell membrane charge from –70 mV to +40 mV, requiring specific changes in ionic concentrations within the cell to balance the external environment. This change is caused by a decrease in potassium concentration and an increase in sodium concentration inside the cell. The response to the depolarization potential increases the permeability of the membrane at the point of initiation of stimulation, which allows positively charged Na+ ions to quickly penetrate into the cell.

Positive action potential plays an important role in the transmission of nerve impulses in the body. The fast depolarization phase ensures impulse transmission along the axon, and the fast repolation phase ensures the restoration of depolarized membranes to their original polarized state

Basics of the depolarization phase of the action potential

The depolarization phase is the most active period of electrophysiological processes during cell operation, which is responsible for the distribution of sodium and potassium inside and outside the neuron. As a result of this phase, three phases are formed: the excitation phase (phase

Depolarization phase The depolarization potential is the immediate “window” of the phase when an artificial impulse triggers the movement (in the form of a throw) of each charged ion across the membrane. When it reaches the opposite side, it becomes an additional dipole, and this effect spreads throughout the cell. The depolarization period is the period through which the membrane restores its electrical polarization to its original values; The duration of this period is usually 1–3 ms. The first stage of the depolarization potential is primary depolarization. The primary shock is the first current of force in any direction.