Fig. 3.

Effect of various pharmacological interventions on P2X4 responses and on the inhibition mediated by CORM-2. Data in this figure were acquired in the conventional whole-cell patch-clamp configuration. In all cases, protocols were as those shown in Fig. 1a, with three control 10 μM ATP applications followed by 1-min pre-incubation of drugs before a fourth ATP application. In each case, mean responses shown were obtained by expressing the fourth response in the presence of drug as a percentage of the third control response. In all cases, data shown represent mean (±s.e.m.). a Effect on P2X4 currents of applications of the following: 30 μM CORM-2 (n = 24), 10 μM amitriptyline + 30 μM CORM-2 (n = 3), 20% CO gas (n = 6), and 300 μM product control (n = 3). b Effect on P2X4 currents of 100 μM 8-Br-cGMP (n = 3) and 10 μM ODQ + 30 μM CORM-2 (n = 3). c Effect on P2X4 currents of 100 μM KCN (n = 8) and 100 μM KCN + 30 μM CORM-2 (n = 6). Also shown are the effects of 30 μM CORM-2 following the inclusion of 2 mM DTT (n = 3) or 100 μM H₂O₂ (n = 5) within the patch pipette and of pre-loading of cells with 1 mM N-acetylcysteine (NAC) for 1 h before patching (n = 4). d Effect on P2X4 currents of 2 μM rotenone (n = 3), 2 μM rotenone + 30 μM CORM-2 (n = 2), 3 μM antimycin A (n = 5), 3 μM antimycin A + 30 μM CORM-2 (n = 8), 30 nM stigmatellin (n = 4), 30 nM stigmatellin + 30 μM CORM-2 (n = 5), and the effect of 30 μM CORM-2 on HEK-P2X4 ρ⁰ cells (n = 5)