Skip to main content
. Author manuscript; available in PMC: 2018 Oct 1.
Published in final edited form as: Pain. 2017 Oct;158(10):1938–1950. doi: 10.1097/j.pain.0000000000000993

Figure 5. Intra-vlPAG administration of α7 nAChR antagonists block PHA-543613 mediated antinociception.

Figure 5

A. Time course of the nocifensive responses during the formalin test. To assess whether the effects of focal PHA-543613 infusion were mediated by α7 nAChR activation in the vlPAG, rats received intra-vlPAG injections of αBGT (1.5 pmol, inverted, filled triangles, n=6) or MLA (90 pmol, filled diamonds, n=6), followed by PHA-543613 (3 nmol). Pretreatment with αBGT or MLA was 30 or 10 min before formalin injection, respectively. PHA-543613 was focally infused 5 min before formalin injection. Responses to vehicle (circles) and PHA-543613 alone (triangles) from Figure 4 are included for comparison. For clarity, the time course of nocifensive responses to MLA and αBGT were not included in this graph. B. Mean duration of Phase II nocifensive behavior. Pretreatment with either MLA or αBGT completely blocked the antinociceptive effects of PHA-543613 during Phase II of the formalin test (Holm-Sidak’s multiple comparisons test: *** p<0.001). The shading within each bar illustrates the proportion of time favoring (white), lifting (gray), or licking (black). Pretreatment with antagonists alone (MLA: n=6; and αBGT: n=5) showed no difference relative to vehicle.