Brain Dopaminergic Signaling in Opioid Use Disorders
- Conditions
- Normal PhysiologyOpioid Use Disorders
- Interventions
- Registration Number
- NCT03190954
- Lead Sponsor
- National Institute on Alcohol Abuse and Alcoholism (NIAAA)
- Brief Summary
Background:
The chemical messenger dopamine carries signals between brain cells. It may affect addiction. Heavy use of pain medicines called opioids may decrease the amount of dopamine available to the brain. Researchers want to study if decreased dopamine decreases self-control and increases impulsiveness.
Objective:
To learn more about how opiate use disorder affects dopamine in the brain.
Eligibility:
Adults 18-80 years old who are moderate or severe opiate users
Healthy volunteers the same age
Design:
Participants will first be screened under another protocol. They will:
* Have a physical exam
* Answer questions about their medical, psychiatric, and alcohol and drug use history
* Take an MRI screening questionnaire
* Give blood and urine samples
* Have their breath tested for alcohol
Participants will have up to 3 study visits.
They will have 2-3 positron emission tomography (PET) scans. A radioactive chemical will be injected for the scans. Participants will lie on a bed that slides in and out of the donut-shaped scanner. A cap or plastic mask may be placed on the head.
Vital signs will be taken before and after the PET scans.
Participants will get capsules of placebo or the study drug. They will rate how they feel before, during and after.
Participants will have their breath and urine tested each day.
Participants will have magnetic resonance imaging (MRI) scans. They will lie on a table that slides into a cylinder in a strong magnetic field. They may do tasks on a computer screen while inside the scanner.
Participants will have tests of memory, attention, and thinking.
Participants will wear an activity monitor for one week....
- Detailed Description
Objectives: Primary objective is to assess whether the balance between dopamine D1 (D1R) and D2 receptors (D2R) signaling in striatum is disrupted in participants with an opioid use disorder (OUD) who are on opioid agonist medication (MAT+: methadone or buprenorphine) relative to OUD participants treated with the opioid antagonist medication naltrexone and OUD participants in recovery and not being treated with medications (MAT-). Secondary objectives are to assess how striatal D1R to D2R availability (assessed with PET) influences: (1) striatal dopamine (DA) release; (2) the function of brain reward and self-control networks (assessed with task fMRI activation and with resting functional connectivity, RFC) and (3) behavior (locomotor activity and neuropsychological tests); (4) to assess if DA increases, as induced by oral methylphenidate (MP), improve the function of brain reward and control networks in OUD; and (5) to assess if there is recovery after protracted treatment (comparing treated and non-treated) by repeating fMRI at 6 month follow-up.
Study population: We will complete studies in 180 (n=180) subjects: N=60 healthy control adults and N=120 OUD participants (60 MAT+, 30 naltrexone-treated and 30 MAT-) aged 18-80 (male/female) will be included.
Design: Single-blind. Participants will undergo three scans with positron emission tomography (PET): one with \[11C\]NNC-112 to assess baseline D1R, another with \[11C\]raclopride after placebo to assess baseline D2R and a third one with \[11C\]raclopride after MP administration (60mg oral) to assess striatal DA release (assessed as the difference in specific binding of \[11C\]raclopride between baseline and MP). In addition, participants will undergo two imaging sessions with MRI to assess functional reactivity to drug-cues and to a measure of self-control (delayed discounting task), to assess RFC and to obtain structural brain measures (including diffusion tensor imaging, DTI). One of the sessions will be done under baseline conditions (no drug administered) and the other after MP (about one hour after the \[11C\]raclopride MP scan is completed). Neuropsychological tests (NP) and accelerometers will be used to assess cognitive performance and locomotor activity respectively.
Outcome Measures: Main outcome: (1) Differences in D1R to D2R striatal ratio between participants with an OUD and controls and between MAT+, naltrexone, and MAT- groups. Secondary outcomes: Correlations between striatal D1R to D2R and (1) striatal DA release; (2) fMRI activation in reward and controls networks (assessed with cue-reactivity and delay discounting tasks, and with RFC) and (3) NP performance and locomotor activity. (4) Differences in fMRI activation and RFC after MP when compared with baseline measures.
Recruitment & Eligibility
- Status
- RECRUITING
- Sex
- All
- Target Recruitment
- 360
Not provided
Not provided
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- SINGLE_GROUP
- Arm && Interventions
Group Intervention Description [11C]raclopride plus drug [11C]NNC-112 Methylphenidate 60 mg. po will be given 60 minutes prior to \[11C\]raclopride scan to measure striatal dopamine release. MRI scan to follow end of PET scan. Subject blind as to drug administration. [11C]NNC-112 [11C]NNC-112 \[11C\]NNC-112 PET scan obtained without any drug intervention to measure dopamine D1 receptors. Blind N/A [11C]raclopride plus placebo [11C]NNC-112 Placebo (po) will be given 60 minutes prior to \[11C\]raclopride scan to measure baseline dopamine D2 receptors. MRI scan to follow end of PET scan. Subject blind as to drug administration. [11C]raclopride plus drug [11C]raclopride plus drug Methylphenidate 60 mg. po will be given 60 minutes prior to \[11C\]raclopride scan to measure striatal dopamine release. MRI scan to follow end of PET scan. Subject blind as to drug administration. [11C]raclopride plus placebo [11C]raclopride plus placebo Placebo (po) will be given 60 minutes prior to \[11C\]raclopride scan to measure baseline dopamine D2 receptors. MRI scan to follow end of PET scan. Subject blind as to drug administration.
- Primary Outcome Measures
Name Time Method Differences in D1R to D2R striatal ratio and in DA release between participants with an OUD and controls and between MAT+, naltrexone, and MAT- groups. End of study To assess whether the balance between D1R and D2R in striatum and in DA release is disrupted in participants with an opioid use disorder (OUD) who are being treated with an opioid agonist medication (MAT+), those treated with an opioid antagonist medication (naltrexone) and OUD participants who are not being treated with medications (MAT-).
- Secondary Outcome Measures
Name Time Method 1) To assess the impact of disruptions on striatal D1R to D2R availability on: DA release; Function of brain reward and control networks; Behavior.2) To assess if DA increases as achieved with oral MP influence the brain functional m... End of study DA release (assessed with \[11C\]raclopride and the MP challenge strategy). Function of brain reward and control networks (assessed with fMRI with task activation and with RFC). Behavior (assessed with NP and actigraphy).
2) To assess if DA increases as achieved with oral MP influence the brain functional measures. End of study Assess the association between striatal D1R to D2R availability and striatal DA release. Assess how D1R and D2R relate to behavior (locomotor activity and NP performance).
3) To assess if there is recovery after protracted treatment (comparing treated and non-treated) by repeating fMRI at 6 month follow-up. End of study Determine if the brain recovers with protracted abstinence as assessed by recovery of resting brain networks and brain activation responses to stimulation.
Trial Locations
- Locations (1)
National Institutes of Health Clinical Center
🇺🇸Bethesda, Maryland, United States