Figure 3.

Nicotine withdrawal evaluated in drug-free fish or fish that had been nicotine pre-exposed to nicotine (1 mg/L/), 10 min after treatment with the non-selective nAChR antagonist mecamylamine (mec) (1 mg/kg i.m.) or vehicle (saline). Behaviour was evaluated in the swimming tank for 5 min, every min for 30 s, in terms of the percentage of animals showing freezing (a) and the number of crossed lines (b). Data are mean ± SEM except for freezing (%). Comparisons were performed using Fisher’s exact probability test or unpaired Student’s t test. WDW=withdrawal. Mec= mecamylamine. N = 10 animals for each group. *p < 0.05vs all the remaining groups; ^&&p <0.02 vs drug-free vehicle and drug-free mec.