highly significantP < 0.001
The effect of the MPEP injections in nicotine-treated rats on responding on the active lever was more highly significant than that measured in the saline-treated rats (nicotine × MPEP F (2,20) = 10.3, P < 0.001).
The effect of the MPEP injections in nicotine-treated rats on responding on the active lever was more highly significant than that measured in the saline-treated rats (nicotine × MPEP F (2,20) = 10.3, P < 0.001).
The difference in the effects of MPEP on responding on the inactive lever between the saline- and nicotine-treated rats approached significance ( F (2,20) = 3.0, P = 0.073).