Figure 1

Prolonged membrane potential change of ACC neurons after digit amputation. A. Light photomicrograph of a pyramidal neuron (square) in the ACC intracellularly stained with neurobiotin after recording. B. High magnification of the labeled pyramidal neuron in Figure A. C. Representative recordings showing the response of ACC neuron to the contralateral third digit amputation. The upper panel is the membrane potential intracellularly recorded from a pyramidal neuron, the middle panel is the intracellularly applied hyperpolarizing current pulses (1 Hz, -0.5 nA, 200 ms), the lower panel is the simultaneous extracellular recording of DC potential in the ACC region. The arrows indicate the time of digit amputation. Approximately 2 min after amputation, the baseline membrane potentials from both recording quickly depolarize for approximately 50 mV and gradually returned to the control level in about 55 min.