Figure 5.

Neuronal KARs expressed by nociceptive DRG neurons are inhibited by PMP. A, Representative glutamate-evoked currents recorded from acutely isolated DRG neurons in control conditions (black lines) or those in the presence of 30 µm PMP (purple line) or 30 µm GYKI-53655 (blue line). Top, The gray bar shows the timing of glutamate application (100 ms). Thirty micromolar PMP almost eliminates the current, whereas the same concentration of GYKI-53655 shows little effect. B, Mean amplitudes of currents evoked from DRG neurons normalized to DMSO (0.3%) controls at a range of PMP concentrations were best fit with a logistic curve with variable IC₅₀ and Hill slopes. Inhibition-response curves of the percent inhibition of KARs in the DRG neurons at a range of PMP concentrations. The IC₅₀ value and 95% confidence interval are shown in Table 1.