Skip to main content
. 2020 Jan 14;13:292. doi: 10.3389/fnbeh.2019.00292

Figure 4.

Figure 4

(A) Schematic diagram of the experiment. (B) Escalation of oxycodone intake in HS rats. *p < 0.05, **p < 0.01, vs. day 1. (C) Effect of VK4116 in HS rats (within-subjects design). The upper panel (a) represents responses at the active lever. The lower panel (b) represents responses at the inactive lever. **p < 0.01, ***p < 0.001, vs. 0 mg/kg; ###p < 0.001, vs. first day of oxycodone self-administration. (D) Development of mechanical hyperalgesia after the escalation of oxycodone self-administration in HS rats. **p < 0.01, vs. baseline (BSL). (E,F) Effect of VK4116 on oxycodone withdrawal-induced hyperalgesia. The data are presented as grams of force applied. (E) **p < 0.01, vs. 0 mg/kg and as a percent change from baseline pre-oxycodone. (F) **p < 0.01, vs. BSL; ##p < 0.01, vs. 0 mg/kg.