Slide 18

The Afterhyperpolarization is Mediated by an Increase in K+ Conductance

The reversal potential of the current underlying the slow AHP was examined in hybrid-voltage clamp in which action potentials were induced in current clamp mode and then the amplifier was switched to voltage clamp mode and the resulting slow outward current was measured at different membrane potentials (Left, B,C; Right, A-C). The slow outward current was associated with an increase in membrane conductance and reversed at around EK in both normal and high potassium solutions (Right, A,B,C).