Figure 1.
The intrinsic properties of an MSO principal neuron from a P21 gerbil. A, Responses to a family of 100 ms current pulses (–2 to 2.8 nA; 0.2 nA steps). The resting membrane potential was –58 mV. The universal response of MSO principal neurons to a suprathreshold depolarizing current step was a single action potential with fast repolarization (top and middle panels). Rapid voltage responses reflect a short membrane time constant, measured using a single exponential fit of a small hyperpolarizing voltage response (bottom panel). B, Peak (triangles) and steady-state (circles) V–I plots generated from the voltage responses shown in A indicate that this neuron also had a low input resistance. Input resistance was obtained from the slope of the V–I plot between 0 and 10 mV below rest (Rinput(pk) = 8 MΩ, Rinput(ss) = 5 MΩ). C, Responses to synaptic stimulation in another cell (P19). MSO principal neurons followed high-frequency synaptic stimulation without temporal summation.