The Effects of Δ 9 ‐Tetrahydrocannabinol (THC) Drug History on THC Taste and Place Conditioning
Briana J. Hempel, Alison Wakeford, Matthew M Clasen, Mary A Friar, Anthony L Riley
The FASEB Journal April 1, 2016 DOI: 10.1096/fasebj.30.1_supplement.703.8 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Population | Male Sprague-Dawley rats |
| Intervention | THC |
| Dose | 3.2 mg/kg pre-exposure; 0, 1, or 3.2 mg/kg in conditioning |
| Duration | 12 days pre-exposure, followed by conditioning and final tests |
| Topics | Cannabis |
| Key findings | THC induced robust taste avoidance but no place conditioning. Pre-exposure to THC attenuated the taste avoidance but did not affect place conditioning, suggesting residual aversive effects limit THC's weak rewarding properties. |
Abstract
Rationale Δ 9 ‐Tetrahydrocannabinol (THC) produces both aversive and rewarding effects in animal models. Given that the balance between a drug's affective properties is thought to underlie its abuse potential, it is important to consider these properties of THC and how they (and their balance) are impacted by various factors. In this context, previous studies have examined the effect of THC history on the aversive and rewarding effects of THC. However, such assessments have been made in different animals under different experimental procedures, making it difficult to assess the relative contribution of either affective property to abuse vulnerability.
Methods: In the present experiment, male Sprague‐Dawley rats were administered six pre‐exposure injections (3.2 mg/kg THC) over 12 days. This was followed by a combined taste avoidance/place preference procedure in which a novel saccharin solution and environment were paired with THC (0, 1 or 3.2 mg/kg). Changes in preferences and aversions for the drug‐paired stimuli were evaluated in final place and taste conditioning tests.
Results: Relative to control subjects, THC produced robust taste avoidance, but did not induce place conditioning. Pre‐exposure to THC attenuated THC‐induced taste avoidance and had no effect on place conditioning with THC.
Conclusions: Similar to prior work, THC induced robust and dose‐dependent taste avoidance. The failure to see THC‐induced place preferences is likely due to the aversive effects of THC masking its rewarding properties. Although THC pre‐exposure weakened the aversive effects of THC (as evidenced in the attenuated taste avoidance), some avoidance was still evident (THC‐injected animals drank less than controls). This suggests that the failure to see a change in THC‐induced place preferences following THC pre‐exposure was a function of its residual aversive effects limiting its relatively weak rewarding properties. These findings support the view that the interaction of reward and aversion is important in behavioral displays of the affective properties of abused drugs. Support or Funding Information This research was supported by a grant from the Mellon Foundation to Anthony Riley
Comparable studies
Other preclinical and animal studies on cannabis, most cited first.