Figure 6.

Inflammatory pain does not affect lever pressing and time to complete the instrumental task under FR2 schedule of sucrose reinforcement. A, Schematic of the experimental design. B, Effect of CFA injection on correct and incorrect FR2 responding for sucrose pellets. Data are mean ± SEM of the number of correct and incorrect responses of the control and CFA-treated rats during the training period and 48 and 72 h after saline or CFA injection. No statistical differences were observed in the number of correct or incorrect responses before and after treatment or between groups (n = 5 or 6 per group). C, Effect of CFA on time to complete the sucrose self-administration under an FR2 schedule of reinforcement during the training period and after CFA (red) or saline (black) injection. Time (mean ± SEM in minutes) to complete the session by self-administering 60 sucrose pellets is represented for each session. No differences were detected before and after CFA or saline injection and between CFA and saline-treated rats. n = 5 or 6 per group.