Figure 2

Bay K8644 enhanced pregabalin-insensitive current suggesting that L-type Ca²⁺ channels are still available for modulation by the 1,4-dihydropyridine agonist. A) Bar chart shows data for mean calcium current amplitudes measured at the peak of the inward current (open bars) and at the end of a 100 ms voltage step command to 0 mV (solid bars, n = 6). Data under control condition (Con) in the presence of 2.5 μM pregabalin (PGB) and in the presence of both pregabalin (2.5 μM) and Bay K8644 (1 μM) are shown. B) The inset traces show voltage and Ca²⁺ current records under control conditions, inhibition in the presence of 2.5 μM pregabalin (PGB) and enhancement of the Ca²⁺ current during continued application of pregabalin with Bay K8644 present (Bay K & PGB). C) Shows the current inhibited by pregabalin, (obtained by subtracting the net current recorded in the presence of pregabalin from the net control current). D) Shows the additional current produced by Bay K8644, (obtained by subtracting the net current recorded in the presence of pregabalin from the net current recorded in the presence of both pregabalin and Bay K8644).