Fig. 3. Differential effect of α-dendrotoxin on IKL in the afferent dendrite versus the spiral ganglion soma. (A~D) ANF dendrite recording (7~14-day-old rat cochlea) before and during application of 100~200 nM α-DTX. (C) Current responses to 200 ms voltage steps from -84 to -34 mV before and during application of α-DTX (5 min). External solutions with TTX (1 μM), CdCl2 (200 μM), ZD7288 (50 μM) and CNQX (10 µM). (D) Diary plot of the outward current measured at 20 ms into the voltage step; after leak subtraction. Rundown of the outward current was observed during recordings (fit by a line). Values extrapolated from this linear fit were used as control values for comparison to the current amplitudes in α-DTX. 27% of the outward current was inhibited by α-DTX in this recording. (E) Summarized results for 6 afferent dendrite recordings. (F~I) Spiral ganglion soma recording (1-day-old rat cochlea) before and during application of 200 nM α-DTX. (H) Current responses to voltage steps from -84 to -34 mV before and during application of α-DTX (5 min). (I) Diary plot of the outward current; after leak subtraction. There was no significant rundown in control. 88% of the outward current was blocked by α-DTX. (J) Summarized results for 3 spiral ganglion neuron soma recordings.
© Exp Neurobiol
