Rationale. Alcohol use disorders (AUDs) and tobacco dependence are frequently identified as co-morbid. Although less than 20% of the general population smokes, over 80% of people with AUDs are considered daily smokers. In fact, people with AUDs are more likely to die from smoking-related health issues, than from alcohol related health issues. Surprisingly, there is very little evidence that alcohol and nicotine are concurrently self-administered in pre-clinical models. We hypothesized that low doses of nicotine that enhancing responding for other rewards would be self-administered and enhance self-administration of alcohol.
Objective. The goal of this study was to determine if low-doses of nicotine, typically not self-administered alone, would promote alcohol self-administration in a concurrent access paradigm.
Method. Alcohol preferring rats (females) were requested from the University of Indiana Medical School breeding facility. They were randomly assigned to one of three groups – NIC-Alone, ALC-Alone, or ALC+NIC. All rats were fluid restricted and shaped to lick for water at two sipper tubes that could record lick responses and deliver aliquiots of fluid into the sipper tube via a solenoid valve. After shaping, rats were instrumented for IV self-administration. During self-administration tests, rats in the ALC-Alone received access to oral ethanol (15% v/v) for meeting the schedule of reinforcement at one sipper tube (e.g., right) and saline infusions for meeting the schedule of reinforcement at the other sipper tube (e.g., left). The NIC-Alone group received IV nicotine infusions (15 ug/kg/inf) and oral licorice (1%) for meeting the schedule of reinforcement at one sipper tube (e.g., left) and oral water for meeting the schedule of reinforcement at the other sipper tube (e.g., right). The ALC+NIC group received IV nicotine and oral licorice for meeting the schedule of reinforcement on the left sipper, and oral ethanol for meeting the schedule of reinforcement on the right sipper. Price manipulations for nicotine were performed by adjusting the schedule of reinforcement on the sipper associated with nicotine infusions.
Results. During acquisition, nicotine did not enhance alcohol self-administration – alcohol intake was comparable between ALC-Alone and ALC+NIC rats. In addition, alcohol did not enhance nicotine self-administration as responding for NIC was comparable between ALC+NIC and NIC-Alone rats. However, when the price of nicotine was manipulated, alcohol created a greater demand for nicotine, as indicated by higher rates of nicotine consumption with increases in price. Manipulating the price of nicotine did not alter demand for alcohol.
Conclusion. The interaction between alcohol and nicotine reinforcers may depend on changes in demand for nicotine. Future studies should investigate whether demand for alcohol is altered by concurrently available nicotine infusions.
*the first and second authors contributed equally to this project
| Identifer | oai:union.ndltd.org:ETSU/oai:dc.etsu.edu:asrf-1377 |
| Date | 12 April 2019 |
| Creators | Kosky, Madison M, Harryman, Dustin C, Smith, Amanda L, Hernandez, Liza J, Deehan, Gerald A, Palmatier, Matthew |
| Publisher | Digital Commons @ East Tennessee State University |
| Source Sets | East Tennessee State University |
| Detected Language | English |
| Type | text |
| Source | Appalachian Student Research Forum |
Page generated in 0.0021 seconds