Effects of Cocaine Self-Administration on Food-Reinforced Responding Using a Discrete Trial Procedure in Rats
| Autor: | David C.S. Roberts, W J Lynch |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Male
Reinforcement Schedule Time Factors Light medicine.drug_class media_common.quotation_subject Rats Sprague-Dawley Discrete trials Animal model Cocaine Dopamine Uptake Inhibitors medicine Animals media_common Pharmacology Analysis of Variance Behavior Animal Local anesthetic Addiction Darkness Rats Behavior Addictive Psychiatry and Mental health Food Anesthesia Conditioning Operant Self-administration Psychology Reinforcement Psychology |
| Zdroj: | Neuropsychopharmacology. 29:669-675 |
| ISSN: | 1740-634X 0893-133X |
| DOI: | 10.1038/sj.npp.1300363 |
| Popis: | Cocaine addiction has been characterized by a shift from controlled to uncontrolled and compulsive drug use. Using novel self-administration procedures, we attempted to model this transitional phase and characterize the behavioral changes that underlie it. We chose to use food-reinforced responding across the light/dark cycle as an indicator of the degree to which cocaine was disrupting ongoing behavior as a potential measure of dysregulation. Four groups of rats (n=5-6) were given 24-h access to cocaine (1.5 mg/kg/inj) available in 2, 3, 4, or 5 discrete trials/h. All rats were given continuous access to a second lever that resulted in the delivery of a 45 mg food pellet under a fixed ratio 1 schedule. The results showed that under low access conditions (eg 2 discrete trials/h), both food- and cocaine-reinforced responding were diurnally regulated and occurred coincidentally. As access to cocaine was increased, there was a progressive disruption in the diurnal control over both food- and cocaine-maintained responding. High access conditions also produced transient decreases in the total levels of food-reinforced responding. These findings suggest that high access to cocaine under the discrete trial cocaine self-administration procedure produces a transient disruption in the diurnal control over behavior maintained by food and that the level of control (or loss of) may be a useful marker of dysregulation. |
| Databáze: | OpenAIRE |
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