Antinociceptive Effects and Interaction Mechanisms of Intrathecal Pentazocine and Neostigmine in Two Different Pain Models in Rats

Figure 2

(a-f). Intrathecal injection of pentazocine (3–100 μg) and neostigmine (0.3–10 μg) induced a dose-dependent inhibition against the formalin-induced pain responses in both phases. (g-h). Injecting pentazocine or neostigmine attenuated the plantar incision-induced mechanical allodynia. (i-k). Dose-response curves of intrathecal pentazocine and neostigmine for flinching during phase I (i) and phase II (j) in the formalin test (k). Data are expressed as the maximal possible effect (% MPE). Each point on the graph represents the mean ± SEM. Compared with the saline group, , , , n = 10 rats in each group).

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