Fig. 3. Blockade of the pinch-induced withdrawal response after perisciatic nerve injection of a combination of lidocaine (0.5%, 1%, and 2%) and 0.2% QX-314; lidocaine alone (0.5%, 1%, and 2%) and QX-314 (0.2%) alone. Note that application of QX-314 alone (0.2%) did not produce detectable changes in the response to the pinch. Grading was as follows: 3 = complete block, no withdrawal, no vocalization; 2 = partial block, vocalization accompanied with slow withdrawal and flexion of the leg; 1 = minimal block, rapid flexion of the leg, or other escape response with loud vocalization; 0 = baseline. n = 8 for each group.