Figure 5.

Altered pain responses in FAAH^−/− mice. (A) FAAH^−/− mice (filled columns) exhibited prolonged response latencies in both the tail-immersion (n = 48, 50, and 62 for FAAH^+/+, FAAH^+/−, and FAAH^−/− genotypes, respectively) and hot plate (n = 12–15 mice per group) tests for thermal pain sensation relative to FAAH^+/+ (open columns) and FAAH^+/− mice (hatched bars; for hot plate data with FAAH^+/− mice, see Fig. 6B Left). (B) Duration of licking during the early phase of the formalin test was reduced in FAAH^−/− mice (filled columns) relative to FAAH^+/− (hatched columns) and FAAH^+/+ (open columns) mice; n = 8–10 mice per group. **, P < 0.01 and ***, P < 0.001 for FAAH^−/− versus FAAH^+/− or FAAH^+/+ mice (planned comparisons). The results are presented as means ± SE.