Nicotine increases sucrose self‐administration and seeking in rats
Associations between nicotine in cigarettes and food consumption may alter the incentive value of food such that food cue‐reactivity is exaggerated during abstinence from smoking. This effect may contribute to the weight gain associated with cessation of smoking. We examined the effects of nicotine (0.4 mg/kg base subcutaneous) paired (NPD) or unpaired (NUP) with 10% sucrose self‐administration (SA; 0.2 ml/delivery, 1 h/day for 10 days) on SA response rate and intake as well as sucrose cue‐reactivity following either 1 or 30 days of forced abstinence. Rats were administered the training dose of nicotine prior to a second, consecutive cue‐reactivity session. NPD rats responded at over three times the rate for sucrose and earned nearly twice the number of sucrose deliveries as NUP rats or saline controls. Sucrose cue‐reactivity was greater after 30 days versus 1 day of forced abstinence for all groups. History of nicotine exposure had no effect on sucrose cue‐reactivity. However, the subsequent injection of nicotine increased sucrose cue‐reactivity only in the NPD groups. There were no abstinent‐dependent effects of nicotine challenge on sucrose cue‐reactivity. A study conducted in parallel with water as the reinforcer revealed a less dramatic effect of nicotine on intake. There was no history or abstinence‐dependent effects of nicotine on water cue‐reactivity. Nicotine increases the reinforcing effects of sucrose and sucrose‐paired cues when nicotine is present. An implication of these findings is that relapse to nicotine (cigarettes) could substantially elevate food cue‐reactivity.
Document Type: Research Article
Affiliations: Department of Psychology and Program in Behavioral Neuroscience, Western Washington University, Bellingham, WA, USA
Publication date: May 1, 2012