Chronic voluntary caffeine intake in male Wistar rats reveals individual differences in addiction-like behavior

Publication date: Available online 24 February 2020Source: Pharmacology Biochemistry and BehaviorAuthor(s): Christine H. Lee, Olivier George, Adam KimbroughAbstractCaffeine is the most widely consumed psychoactive substance in the world. However, there is controversy about whether becoming addicted to caffeine is possible and a lack of well-established animal models to examine caffeine consumption. The present study sought to establish a model of caffeine consumption in Wistar rats, identify different rat populations of caffeine preference, and determine whether extended voluntary caffeine consumption produces compulsive-like caffeine intake and withdrawal symptoms.Male Wistar rats were used throughout the experiment. The optimal concentration of caffeine to maximize caffeine consumption and caffeine preference was determined. Rats were then given continuous access to caffeine, followed by intermittent access. Rats were tested for signs of withdrawal-like behavior by measuring mechanical nociception and irritability-like behavior. Rats were further examined for compulsive-like caffeine consumption.Dose-response testing indicated an optimal caffeine concentration of 0.3 mg/ml. During intermittent access to caffeine, the rats did not escalate their caffeine intake and instead exhibited a decrease in intake over sessions. Three groups of rats were identified based on caffeine preference (high, medium, and low) across continuous and intermittent access. These three groups of ra...

Source: Pharmacology Biochemistry and Behavior - February 24, 2020 Category: Biochemistry Source Type: research