Figure 2

The effect of picrotoxin on neuronal excitation in slices taken from capsaicin-treated rats. A, Examples of optical response time courses in substantia gelatinosa of spinal dorsal horn elicited by various intensities of single-pulse stimulations to the dorsal root in a slice taken from a capsaicin-treated rat. The arrowhead indicates the time when stimulation was applied. B, The mean amplitude of optical responses elicited by the stimulation pulses shown in A in slices taken from normal rats (open circles) and capsaicin-treated rats (filled circles). C, Examples of time courses of optical responses in the substantia gelatinosa of the spinal dorsal horn elicited by a high-intensity single-pulse stimulation to the dorsal root in a slice taken from a capsaicin-treated rat in control (thin line) and picrotoxin (thick line) conditions. The arrowhead indicates the time when stimulation was applied. * P < 0.05.