Prologue: The Ion Channel

A historical overview describes how classic electrophysiological techniques, such as membrane potential measurement, seal formation, and the voltage clamp, have evolved into modern patch-clamp techniques. We show that old ideas from seminal papers on ion channels (i.e., gating, inactivation, ion permeation, ion selectivity) have remained as valid concepts for understanding the molecular properties of ion channels. With the currently available three-dimensional crystal structures of channel proteins, in combination with patch-clamping, novel experimental approaches that focus on the dynamic behavior of channel molecules are undergoing.