Patch-clamp recording from myelinated central axons

Abstract

Axons perform the main fundamental electrical operations of neurons. Emerging near the soma, axons integrate synaptic potentials, convert these into action potentials, and conduct the output signal to the presynaptic terminals. With the establishment of patch-clamp recording techniques in brain slices in combination with high-resolution microscopy, it has now become possible to visually target patch-clamp electrodes to various domains of the axon. This chapter provides an overview of the methodology for obtaining patch-clamp recordings from axons, with a focus on their unmyelinated regions, including the axon initial segment and axonal cut endings. Axonal patch-clamp recordings are a prerequisite for the study of the biophysics and diversity of axonal voltage-gated ion channels; in particular, high-temporal resolution, low-noise voltage recordings offer detailed insights into the fast computational properties of central nervous system axons.