Positron Emission Tomography (PET), raclopride, Tetrahydrocannabinol (THC), cannabis, dopamine
Conditions
Interventions
Healthy subjects will inhale placebo or 8 mg of THC, the main psychoactive ingredient of cannabis, by means of a vaporizer.
Sponsors
Department of Psychiatry
University Medical Center Utrecht
Eligibility
Inclusion criteria
Inclusion criteria: 1. Age between 18 and 45 years; 2. History of mild cannabis use for at least one year ( 4/year); 3. History without further illicit drug use; 4. History without psychotic experiences after cannabis use; 5. Written informed consent of the subject.
Exclusion criteria
Exclusion criteria: 1. Any clinical significant abnormality of any clinical laboratory test, including drug screening; 2. Impaired physical health evaluated by medical history, physical (including neurological) examination and screening laboratory tests; 3. Any major current psychiatric diagnosis on axis-1 of DSM-IV; 4. History of clinically significant psychiatric or neurological illness; 5. History of clinically significant psychiatric or neurological illness in first- or second-degree relatives; 6. History of alcohol and/or drug abuse (DSM-IV criteria); 7. Paranoid ideation or psychoticism on SCL-90; 8. Any subject who received any investigational medication within 90 days prior to the start of the study or who is scheduled to receive an investigational drugs; 9. The use of any medication within three weeks prior to the start of the study, except for paracetamol; 10. Positive HIV or Hepatitis B/C test; 11. Blood donation within 3 months before the first test day; 12. Hb must be => 8 mmol / liter (males) or => 7 mmol / liter (females); 13. Body Mass Index (B.M.I.) between 18 and 28 kg/m2; 14. Claustrophobia; 15. Metal objects in or around the body (braces, pacemaker, metal fragments); 16. Pregnancy and breast feeding; 17. Exposure to radioactivity leading to a yearly cumulative dose of 10 mSv or more.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| After inhalation of THC, dopamine release will be investigated using the [11C]raclopride displacement paradigm. Increase in striatal synaptic dopamine will be measured by the decline in D2 receptor availability to the binding of [11C]raclopride. This binding will be demonstrated using Positron Emission Tomography (PET). | — |
Secondary
| Measure | Time frame |
|---|---|
| Behavioral parameters (BPRS and two VAS questionnaires) and the concentration of plasma THC and its main metabolites will be obtained as well. Vital signs (blood pressure and heart rate) will be measured regularly. | — |
Contacts
Public ContactM.G. Bossong
University Medical Center Utrecht (UMCU), Department of Psychiatry, Heidelberglaan 100, P.O. Box 85500
Outcome results
None listed