Dopamine and Opioid Receptor Antagonists Reduce Cue-induced Reward Responding and Reward Impulsivity

• Status: Completed
• Trial end date: 2014-04-01
• Target enrollment: 0
• Participant gender: All

Summary

The purpose of this study is to determine how the dopamine and opioid system is involved in reward processing, specifically in cue-induced reward responding and reward impulsivity, using dopamine and opioid receptor antagonists in healthy participants. The investigators predict that particularly the dopamine challenge should alter cue-induced reward responding and reward impulsivity. Such effects would be of high interest for the treatment of disorders which involve impairments of reward processing such as addiction.

• Phase: N/A
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: University of Zurich
• Treatments: Amisulpride; Analgesics, Opioid; Dopamine; Dopamine Agents; Naltrexone; Narcotic Antagonists; Sulpiride; Sultopride

Criteria

Inclusion Criteria:

• Physically and psychiatrically healthy men and women

Exclusion Criteria:

• Serious past brain disease or injury

• Pacemaker or neurostimulator

• Hearing aid

• Surgery to head or heart

• Potential metal parts in body (metal splinters, gun wounds, shrapnel or surgical clips)

• Neurological or psychiatric problems (including alcoholism, depression, schizophrenia, bipolar disorders, anxiety disorder, claustrophobia, or parkinsonian symptoms)

• High blood pressure, low blood pressure, cardiac attack in anamnesis, irregular heart rate

• Epilepsy

• Emphysema, chest problems, or multiple sclerosis

• Respiratory problems (including difficulty breathing through the nose)

• Pregnancy, nursing, or planning pregnancy

• Diabetes

• Acute Hepatitis

• Allergy or sensitivity to lactose

• Allergy or sensitivity to amisulpride or naltrexone

• Breast cancer or current tumors

• Insufficiency of liver or kidney

• Past use of opiates or other drugs that may interact with amisulpride or naltrexone (such as stimulants)

• Currently taking medications known to interact with amisulpride or naltrexone (including medicines used to treat irregular heart rhythm such as quinidine, disopyramide, amiodarone and sotalol, cisapride, antibiotics such as erythromycin and pentamidine, levodopa, thioridazone (an antipsychotic), or methadone)