Voltage-clamp studies in axons: Macroscopic and single-channel currents

Abstract
This chapter describes macroscopic membrane currents measured in amphibian and mammalian nodes of Ranvier with the voltage-clamp method. These results are compared with those of single-channel recordings, which provide important data on channel characteristics in myelinated axons. The results obtained from the calculation of the action potentials with voltage-clamp data obtained from frog, rat, and human nerve fibers are also reviewed. It is shown that the properties of the various new ionic channel types detected with the patch-clamp technique help explain previously unsolved problems concerning the ionic basis of accommodation, resting potential, and various pathophysiological phenomena.