Fig. 8

Effects of the PKG inhibitor KT 5823. a Scheme on the left describes the protocol of anantin (500 nM, 2 h) and the selective PKG inhibitor KT 5823 (1 µM, 2 h) co-application. Histograms (middle) show mean P2X3 current density values in control and after application of KT 5823 (1 µM, 2 h), anantin (500 nM, 2 h), or their combination (n = 33, 30, 40, 34, respectively; *p < 0.05, Kruskal–Wallis test). Representative current traces of P2X3 receptors for each experimental condition are shown on the right and were evoked by 2 s pulses of 10 µM α,β-meATP. KT 5823 produces anantin-like effect on P2X3 currents and shows no additivity when co-applied with anantin. b Representative example of Western immunoblotting with P2X3 pSer and P2X3 anti-P2X3 receptor antibodies (left) shows the amount of P2X3 receptors in control and after application of KT 5823 (1 µM, 2 h), anantin (500 nM, 2 h) or their combination; histogram on the right quantifies P2X3 pSer (relative optical density values) for each experimental condition (n = 3; *p < 0.05, Kruskal–Wallis test). Note that KT 5823 is as efficient as anantin in lowering the amount of P2X3 pSer. c Representative example of Western immunoblotting (on the left) and the histograms (on the right) summarize the amount of P2X3 receptors and P2X3 pSer in lipid rafts and non-raft membrane fractions in control and after application of KT 5823 (1 µM, 2 h), anantin (500 nM, 2–3 h), or their combination (n = 3; *p < 0.05, Kruskal–Wallis test). KT 5823 acts like anantin, causing P2X3 receptors redistribution to the lipid raft membrane compartment