Measuring Action Potential Propagation Velocity in Murine Cortical Axons.

Measuring the action potential (AP) propagation velocity in axons is critical for understanding neuronal computation. This protocol describes the measurement of propagation velocity using a combination of somatic whole cell and axonal loose patch recordings in brain slice preparations. The axons of neurons filled with fluorescent dye via somatic whole-cell pipette can be targeted under direct optical control using the fluorophore-filled pipette.

SUMOylation of Na1.2 channels regulates the velocity of backpropagating action potentials in cortical pyramidal neurons.

Voltage-gated sodium channels located in axon initial segments (AIS) trigger action potentials (AP) and play pivotal roles in the excitability of cortical pyramidal neurons. The differential electrophysiological properties and distributions of Na1.2 and Na1.

Subcellular Distribution of Persistent Sodium Conductance in Cortical Pyramidal Neurons.

Cortical pyramidal neurons possess a persistent Na current ( ), which, in contrast to the larger transient current, does not undergo rapid inactivation. Although relatively quite small, is active at subthreshold voltages and therefore plays an important role in neuronal input-output processing. The subcellular distribution of channels responsible for and the mechanisms that render them persistent are not known.