Related Experiment Video
Updated: Jan 30, 2026

The Adventures of Fundi Intervention Based on the Cognitive and Emotional Processing in Attention Deficit Hyperactive Disorder Patients
Published on: June 12, 2020
Caffeine and cannabinoid receptors modulate impulsive behavior in an animal model of attentional deficit and
Douglas T Leffa1, Samira G Ferreira2, Nuno J Machado2
1Department of Biochemistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
Abstract:
Attention deficit and hyperactivity disorder (ADHD) is characterized by impaired levels of hyperactivity, impulsivity, and inattention. Adenosine and endocannabinoid systems tightly interact in the modulation of dopamine signaling, involved in the neurobiology of ADHD. In this study, we evaluated the modulating effects of the cannabinoid and adenosine systems in a tolerance to delay of reward task using the most widely used animal model of ADHD. Spontaneous Hypertensive Rats (SHR) and Wistar-Kyoto rats were treated chronically or acutely with caffeine, a non-selective adenosine receptor antagonist, or acutely with a cannabinoid agonist (WIN55212-2, WIN) or antagonist (AM251). Subsequently, animals were tested in the tolerance to delay of reward task, in which they had to choose between a small, but immediate, or a large, but delayed, reward. Treatment with WIN decreased, whereas treatment with AM251 increased the choices of the large reward, selectively in SHR rats, indicating a CB1 receptor-mediated increase in impulsive behavior. An acute pre-treatment with caffeine blocked WIN effects. Conversely, a chronic treatment with caffeine increased the impulsive phenotype and potentiated the WIN effects. The results indicate that both cannabinoid and adenosine receptors modulate impulsive behavior in SHR: the antagonism of cannabinoid receptors might be effective in reducing impulsive symptoms present in ADHD; in addition, caffeine showed the opposite effects on impulsive behavior depending on the length of treatment. These observations are of particular importance to consider when therapeutic manipulation of CB1 receptors is applied to ADHD patients who consume coffee.
Related Concept Videos
Attention-Deficit/Hyperactivity Disorder
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings....
REM Sleep Behavior Disorder
RBD is significantly associated with...
Impulse
Additionally, it can be shown that the...
Impulse Response
Kirchhoff's law forms an input signal equation, with the capacitor's current and voltage providing the output. Substituting the current and dividing by RC yields a differential equation. The output for an impulse input is the impulse...
The Two-State Receptor Model
The binding affinity of a drug determines its interaction with...
Internal Receptors

