Question

If a drug partly blocks a membrane potassium channels what happens to the action potential?

Answer 1

• Action potentials are known to be the source of communication transmitted from one part of the body to another through neurons, which are commonly represented as electrical signals.
• The main principle underlying this mechanism is regulated by ionic channels through selective permeability of ions with respect to the concentration gradient at a specific point of time, calculated by the amount of ions present outside and inside of the cell.
• The primary role of potassium channels in cardiac action potentials is cell repolarization.Potassium-channel blockers comprise the Class III antiarrhythmic compounds according to the Vaughan-Williams classification scheme.
• These drugs bind to and block the potassium channels that are responsible for phase 3 repolarization. Therefore, blocking these channels slows (delays) repolarization, which leads to an increase in action potential duration and an increase in the effective refractory period (ERP).