D1 and D2 Dopamine Receptors in Gambling and Amphetamine Reinforcement

Summary

To determine if:

1. pathological gambling is similar to psychostimulant addiction as reflected by parallel roles for D1 and D2 receptors in gambling and stimulant reinforcement.
2. these parallel roles are linked with gambling pathology or if they are evident in both gamblers and controls.

Conditions

• Pathological Gambling

Interventions

DRUG

Haloperidol

Dose/maximum dose = 3-mg; route = oral. Participants assigned to the haloperidol antagonist group will receive 2 doses (@ 3 mg) on alternate sessions (with minimum of 2 weeks between individual doses). Dose 1: 3 visually identical capsules, each containing 1 mg haloperidol.

DRUG

Fluphenazine

Dose/maximum dose = 3-mg; route = oral. Participants assigned to the fluphenazine antagonist group will receive 2 doses (@ 3 mg) on alternate sessions (with minimum of 2 weeks between individual doses). Dose 1: 3 visually identical capsules, each containing 1 mg fluphenazine.

DRUG

Dexedrine

Dose/maximum dose = 20-mg; route = oral. All participants will receive 2 doses (@ 20 mg) during Phase II - sessions 3, 4, with minimum 1 week between individual doses. Dose 2: when participants reach expected peak blood levels for dose 1, they will receive their second dose. On sessions 3 and 4 (Phase II), the dose will consist of 2 visually identical capsules each containing 10 mg D-amphetamine.

DRUG

Placebo

Dose 1: On alternate sessions (1 and 3 or 2 and 4, depending on counterbalancing) participants will receive 3 visually identical placebo (lactose) capsules. Dose 2: when participants reach expected peak blood levels for dose 1, they will receive their second dose. On sessions 1 and 2 (Phase I), this will consist of 2 dummy capsules, visually identical to those administered for dose 1.

BEHAVIORAL

Slot Machine

15 minute play of a commercial slot machine game in bar-simulated laboratory setting.

Sponsors & Collaborators

• Canadian Institutes of Health Research (CIHR)

  collaborator OTHER_GOV

• Centre for Addiction and Mental Health

  lead OTHER

Principal Investigators

• Daniela Lobo, MD, Ph.D. · Centre for Addiction and Mental Health

Study Design

Allocation

RANDOMIZED

Purpose

DIAGNOSTIC

Masking

TRIPLE

Model

PARALLEL

Eligibility

Min Age

19 Years

Max Age

65 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2009-09-30

Primary Completion

2015-06-30

Completion

2015-09-30

Countries

• Canada

Study Locations