Fig. 3.

Time course of effect of NAX 409-9 (12 mg/kg) in the carrageenan model of thermal hyperalgesia. Mice were evaluated for thermal response latencies at 150, 180, and 210 minutes following carrageenan administration (corresponding to 30, 60, and 90 minutes following administration of NAX 409-9, 12 mg/kg) or vehicle (1% Tween 20/saline). NAX 409-9 was administered such that the time-to-peak effect for the compound (1 hour) corresponded with maximal hyperalgesia following carrageenan administration (approximately 3 hours). (A) Shows the time course of effect of carrageenan administration (administered at time = 0 minute) and treatment with either vehicle (squares) or NAX 409-9 (triangles). Responses in both left (contralateral; filled squares, vehicle; filled triangles, NAX 409-9) and carrageenan-injected (right, ipsilateral; open squares, vehicle; open triangles, NAX 409-9) paws are shown across the time of testing. (B) Shows the area under the curve for each paw (ipsilateral and contralateral) in each group (vehicle or NAX 409-9), normalized to the contralateral paw in vehicle-treated animals (% control). Carrageenan-treated paws show reduced withdrawal latency, with a maximal effect at 210 minutes. NAX 409-9 reversed this reduction in paw withdrawal latency in ipsilateral paws. N = 8 for each group. **P < 0.01 compared with all other groups.