The Modulation of Reward to Nicotine and Ethanol by Sex and Stage of Exposure

Tobacco and alcohol are among the most widely used and abused drugs in America, resulting in disastrous health consequences and a massive resource drain on society. Nicotine (the primary reinforcing component in tobacco) and alcohol are often used together, though there is limited research on exposure to both drugs at the same time. The present study attempted to fill this gap in knowledge by examining the reward for a cocktail of nicotine and alcohol in male and female Long-Evans rats with differing histories of drug exposure. The conditioned place preference paradigm was used to examine the effects of sex as well as the different histories of prenatal and/or adolescent drug exposure on reward for the cocktail. There was a main effect of sex on reward, with males showing a conditioned place preference for the cocktail and females showing no preference. Additional measures of locomotor activity induced by the drug cocktail differed depending on adolescent nicotine exposure, with rats having a previous history of nicotine exhibiting greater total distance travelled after receiving the cocktail. Results of the study indicate a possible moderating role of nicotine with alcohol co-exposure, and suggest that future studies should modify the exposure paradigm to better examine this potential role.