Figure 9

Intracellular photorelease of GTP-γ-S did not alter the sensitivity of DRG neurones to pregabalin. A) Traces showing a Ca²⁺ current attenuated and slowed by intracellular flash photolysis of caged GTP-γ-S (GTP-γ-S) and a Ca²⁺ current showing voltage-dependent partial recovery of GTP-γ-S-evoked inhibition (GTP-γ-S + PP {pre-pulse to +120 mV}). B) Bar chart showing control (Ctrl) data, the inhibitory effects of both intracellular photorelease of GTP-γ-S (GTP-γ-S) and subsequent application of 2.5 μM pregabalin (GTP-γ-S & PGB) on the mean peak Ca²⁺ current amplitude. Inset records show individual Ca²⁺ currents recorded under control conditions, after intracellular photorelease of GTP-γ-S (GTP-γ-S) and after subsequent extracellular application of pregabalin for 3 minutes (GTP-γ-S + PGB). C) Bar chart showing control (Ctrl) data, the inhibitory effects of both 3 minutes extracellular application of 2.5 μM pregabalin (PGB) and subsequent intracellular photorelease of GTP-γ-S in the continued presence of pregabalin (PGB & GTP-γ-S) on the mean peak Ca²⁺ current amplitude. Inset records show individual Ca²⁺ currents recorded under control conditions, after application of pregabalin for 3 minutes (PGB) and after intracellular photorelease of GTP-γ-S (PGB & GTP-γ-S). None of the currents in this figure have been leak subtracted. However, neither pregabalin nor GTP-γ-S altered the leak current.