Heterogeneous Responses to Antioxidants in Noradrenergic Neurons
of the Locus Coeruleus Indicate Differing Susceptibility to Free Radical Content
Figure 4
Effect of DTT treatment on voltage-dependent currents evoked by ramps and pulses. (a) Representative recording of the currents evoked by depolarizing ramps showing the current evoked in ACSF (control solution; solid black line) and the inward (solid light grey) and outward (dashed grey) currents evoked at 180 s after 1 mM DTT application (). (b) I-V plot for the currents presented in a. (c) Mean differential (i.e., DTT-control) with records obtained 180 s after rapid application of DTT showing the inward (solid light grey, 7 of 9 neurons) and outward (dashed grey, 2 of 9 neurons) currents. (d), (e), and (f) were performed in 1 μM TTX background. (d) Representative depolarizing pulse-evoked differential currents obtained by taking the currents in test solution (i.e., 1 mM DTT + 1 μM TTX) and subtracting the corresponding currents in control (i.e., 1 μM TTX) 180 s after DTT application. (e) Averaged I-V plot showing the currents evoked by pulses for control (1 μM TTX—solid black) and the inward (solid light grey) and outward (dashed grey) currents after 180 s of 1 mM DTT application.(f) Mean differential I-V plots (i.e., DTT—TTX) inward (solid light grey, 5 of 10 neurons) and outward (dashed grey, 5 of 10 neurons) after 180 s application of 1 mM DTT. Graph shows mean ± SEM with for (d), (e), and (f).
