Adolescent nicotine exposure fails to impact cocaine reward, aversion and self-administration in adult male rats

作者：Pomfrey Rebecca L^*; Bostwick Tamaara A; Wetzell B Bradley; Riley Anthony L

来源：Pharmacology Biochemistry and Behavior, 2015, 137: 30-37.

DOI：10.1016/j.pbb.2015.08.004

• Conditioned taste avoidance
• Conditioned place preference
• Cocaine self-administration
• Nicotine pre-exposure
• Adolescent drug exposure
• Sprague-Dawley rats

The present experiments examined the effects of adolescent nicotine pre-exposure on the rewarding and aversive effects of cocaine and on cocaine self-administration in adult male rats. In Experiment 1, adolescent Sprague-Dawley rats (postnatal days 28-43) were given once daily injections of nicotine (0.6 mg/kg) or vehicle and then tested for the aversive and rewarding effects of cocaine in a combined conditioned taste avoidance (CTA)/conditioned place preference (CPP) procedure in adulthood. In Experiment 2, adolescent Sprague-Dawley rats were pre-exposed to nicotine then tested for cocaine self-administration (0.25 or 0.75 mg/kg), progressive ratio (PR) responding, extinction and cue-induced reinstatement in adulthood. In Experiment 1, rats showed significant dose-dependent cocaine-induced taste avoidance with cocaine-injected subjects consuming less saccharin over trials, but no effect of nicotine pre-exposure. For place preferences, cocaine induced significant place preferences with cocaine injected subjects spending significantly more time on the cocaine-paired side, but again there was no effect of nicotine history. All rats in Experiment 2 showed clear, dose-dependent responding during cocaine acquisition, PR testing, extinction and reinstatement with no effect of nicotine pre-exposure. These studies demonstrate that adolescent nicotine pre-exposure does not have an impact on cocaine's affective properties or its self-administration at least with the specific parametric conditions under which these effects were tested.

• 出版日期2015-10