Fig. 3.
Some interneurons do not respond to nicotinic agonist. All recordings in this figure are from an interneuron with its cell body in the pyramidal cell layer. A, Membrane responses to depolarizing and hyperpolarizing current injection (120 pA). B, Membrane potential response to pressure application of 3 mm ACh. C, Voltage-clamp recording (VH = −70 mV) measuring the current response to 3 mm ACh. Calibration:A, B, Vertical, 20 mV,horizontal, 200 msec (A) 500 msec (B); C, vertical 20 pA, horizontal 500 msec.