Figure 2

Enhanced pain-related behaviors in orexin neuron-ablated mice.

(A) Von Frey tests for mechanical nociception (DOX(+): n = 16, DOX(−): n = 20). Escape force was measured. (B) Hargreaves tests for heat nociception (DOX(+): n = 12, DOX(−): n = 15). Escape latency was measured. (C) Cold plate tests for cold nociception (DOX(+): n = 12, DOX(−): n = 15). The number of pain related behaviors were counted. (D) Formalin tests for chemical nociception (DOX(+): n = 4, DOX(−): n = 5). The licking and biting time after formalin injection was measured. (E) Quantitative analysis of the formalin test; Phase I: 0–5 min, Phase II: 10–45 min. Data represent the mean ± SEM. Statistical analyses were performed by a Student’s t-test (*p < 0.05, **p < 0.01).