Figure 1.

Examples of APs recorded from mechanoreceptive neurons. (A) Representative intracellular somatic action potential of an A-fiber neuron evoked by electrical stimulation of the dorsal root showing the electrophysiological parameters measured, including: 1, resting membrane potential; 2, action potential duration at base; 3, action potential rise time; 4, action potential fall time; 5, action potential amplitude; 6, AHP duration to 50% recovery; 7, and afterhyperpolarization amplitude below Vm. In addition, maximum rising and falling rates, (dV/dt) max, were measured from the differential trace of the action potential. (B) Somatic action potentials evoked by dorsal root stimulation and recorded intracellularly from 12 mechanoreceptive neurons selected to represent the mean action potential duration values for each of the different groups of neurons in control (upper) and neuropathic (lower) animals. The action potential duration and conduction velocity for each neuron are given below each record. The horizontal lines across the action potentials indicate zero membrane potential.

Abbreviations: HTM, high threshold mechanoreceptive neurons; LTM, low threshold mechanoreceptive neurons.