Imaging Dopamine Release in Depression

October 30, 2019 updated by: Franklin Schneier, New York State Psychiatric Institute

Ventrostriatal Dopamine Release and Reward Motivation in MDD

This study aims to determine whether ventral striatal dopamine release is a mechanism of reward motivation in major depression, whether dopamine release is low in depression, and whether DA release and reward motivation predict response to dopamine-targeted treatment with pramipexole.

Study Overview

Status

Completed

Intervention / Treatment

Detailed Description

Better understanding of the basic neurobiology of mood dysfunction appears necessary to enable further progress in the treatment of depression. Reward motivation (and the closely related construct of "reward learning") is a core neurobehavioral domain.(1,2) In major depressive disorder (MDD), low reward motivation is a key aspect of anhedonia, a cardinal symptom of MDD, and is related to resistance to treatment.(2,3) Although much has been learned about reward motivation's neurobiology and relevance to psychopathology, important gaps in our knowledge have impeded the application of basic science findings to improving treatment of MDD. Reward motivation in healthy subjects involves ventrostriatal (VST) dopamine (DA)(4,5), and reduced reward motivation is linked to MDD and anhedonia.(3,6) These data suggest that VST DA dysfunction might be present in MDD and manifested clinically by anhedonia. While DA neuroreceptor imaging studies have failed to verify this, they have been methodologically compromised. Limitations include imaging methods with poor resolution of functional striatal subregions, MDD samples heterogeneous for antidepressant use, and use of self-report measures of anhedonia, rather than objective behavioral testing of the specific domain of reward motivation. This will be the first study of both VST DA release (by PET imaging) and reward motivation, and will include patients with MDD and healthy volunteers. Reward motivation will be captured and operationalized as reward learning in a probabilistic reward task (prior to imaging). This will clarify if VST DA dysfunction is linked to impaired motivation in MDD. To test clinical implications in MDD patients, we will assess the relationship of VST DA release, reward motivation, and anhedonia to outcome of subsequent open label treatment with the DA D2 receptor agonist pramipexole.

Study Type

Interventional

Enrollment (Actual)

52

Phase

  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • New York
      • New York, New York, United States, 10032
        • New York State Psychiatric Institute

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 50 years (ADULT)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Weight between 44 kg and 115 kg
  • Meets DSM-IV criteria for principal diagnosis of MDD, current major depressive episode, without psychotic features
  • Score of >16 and <29 on 17-item Hamilton Rating Scale for Depression
  • Psychotropic-naïve, as defined by lifetime <2 weeks treatment with antidepressants, anxiolytics or antipsychotics
  • Able to tolerate a treatment-free period during study participation
  • Able to provide informed consent

Exclusion Criteria:

  • A principal diagnosis of any current Axis I psychiatric disorder other than the MDD
  • Lifetime diagnosis of any psychotic disorder, bipolar disorder, mental retardation, attention deficit/hyperactivity disorder, or substance use disorders (including nicotine use disorders)
  • Serious suicidal risk or history of violent behavior which would make participation in the protocol unsafe
  • Any tobacco use in the prior three months (if not already excluded for abuse/dependence by #1)
  • Illicit drug use in the prior three months, as evidenced by history or urine toxicology screen
  • Women who are pregnant, nursing, postmenopausal, or using hormonal methods of birth control
  • Women who are not using an effective birth control method or sexual abstinence during the ten days before the scan
  • Any medical or neurological problem that might affect interpretation of findings or safety of participation (e.g., blood dyscrasias, lymphomas, hypersplenism, endocrinopathies, renal failure or chronic obstructive lung disease, malignancy, neurological diseases of the brain, history of seizures or head trauma), low hemoglobin (Hb < 12 gm/dL in males, Hb < 10.5 gm/dL in females))
  • Blood donation within 4 weeks of study
  • Metal implants or paramagnetic objects in the body that might affect safety of undergoing MRI (e.g., heart pacemaker, shrapnel, bullets, surgical prostheses or surgical clips), as determined in consultation with a neuroradiologist and according to the guidelines set forth in the reference: "Guide to MR procedures and metallic objects" Shellock; Lippincott Williams and Wilkins, NY, 2001
  • More than one major risk factor for coronary artery disease (e.g. hyperlipidemia, sedentary lifestyle). Smokers are already excluded by #4 above, and diabetics by #8 above
  • Systolic blood pressure > 140 or diastolic blood pressure > 90 based on at least two readings at rest
  • History of untoward reaction to amphetamine or other stimulant medication, or pramipexole
  • Any psychotropic treatment in the past 3 weeks (or depot medication in the past 6 months), except for lorazepam,which may be administered as needed prior to imaging day
  • Current, past or anticipated exposure to radiation in the workplace, or participation in nuclear medicine procedures, including research protocols (In case of previous exposure to activity due to research studies, subjects will be eligible if all conditions listed below are fulfilled: 1) The injected dose and dosimetry of the radiotracer are known; 2) Except for research studies, the subject has not been exposed to radiation (workplace and medical); 3) Adding prior exposure to the exposure due to the study will result in a yearly cumulative exposure lower than the FDA limit for research studies
  • Family history of schizophrenia in parents, siblings, or children
  • Ongoing cognitive-behavioral or interpersonal psychotherapy for depression (Supportive therapy is not an exclusion)
  • Ongoing treatment with cimetidine

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: OTHER
  • Allocation: NON_RANDOMIZED
  • Interventional Model: PARALLEL
  • Masking: NONE

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Pramipexole
Six weeks of treatment with oral pramipexole, initiated at 0.25 mg/day and titrated to a maximum daily dose of 2.5 mg.
Dose will be started at 0.125 mg bid, and increased by 0.25 mg/day every 3-4 days to a target range of 1.0 - 2.5 mg/day.
Other Names:
  • Mirapex (brand name)
No Intervention: Healthy Control
Healthy volunteers were matched to MDD group subjects by age, gender, and ethnicity, and will have no lifetime psychiatric disorders.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Hamilton Rating Scale for Depression
Time Frame: Baseline and 6 weeks
Hamilton Rating Scale for Depression (HRSD), 17-item version. This standard scale will be used to assess severity of depression, looking at change in total score from baseline to week 6, rating severity of depression on a scale from 0 (least depression) to 50 (greatest depression)
Baseline and 6 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Snaith Hamilton Pleasure Scale
Time Frame: Baseline and 6 weeks
Fourteen-item self-rated anhedonia scale. Items were comprised of statements that participants rated as "strongly disagree" (1), "disagree" (2), "agree" (3), or "strongly agree" (4). The lowest possible score was 14, the highest possible score was 56.
Baseline and 6 weeks
Change in Temporal Experience of Pleasure Scale - Anticipatory Subscale
Time Frame: Baseline and 6 weeks

A validated self-rated scale shown to assess anticipatory pleasure. It will be used for exploratory analyses of anhedonia.

18 items were measured on a scale of 1 (very false for me) to 6 (very true for me). Higher scores indicate higher pleasure. Item scores were added for a lowest possible score of 18 and highest possible score of 108.

Baseline and 6 weeks
Change in Mood and Anxiety Symptom Questionnaire, Short Form
Time Frame: Baseline and 6 weeks
Change in Mood and Anxiety Symptom Questionnaire, Short Form. A 62-item scale assessing anxiety and depression. Items were measured on a scale of 1-5, higher number indicating higher levels of symptoms.The lowest possible score was 62, and the highest 310.
Baseline and 6 weeks
Change in the Apathy Evaluation Rating Scale
Time Frame: Baseline and 6 weeks
A validated self-rated 18 item scale assessing apathy. Items were rated from 1 (not at all true) to 4 (very true). Higher scores indicate lower apathy, lower scores indicate higher apathy. Lowest possible score is 18, highest possible score is 72.
Baseline and 6 weeks
Change in Clinical Global Improvement - Severity Scale
Time Frame: 6 weeks
Seven-point Likert scale rating clinical severity of mental illness from 1 (least severe) to 7 ( most severe). Physician-rated scale. One item.
6 weeks
Change in Temporal Experiences of Pleasure Scale -- Consummatory Subscale
Time Frame: Baseline and 6 weeks

A validated self-rated scale shown to assess consummatory pleasure. It will be used for exploratory analyses of anhedonia.

18 items were measured on a scale of 1 (very false for me) to 6 (very true for me). Higher scores indicate higher pleasure. Item scores were added for a lowest possible score of 18 and highest possible score of 108.

Baseline and 6 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 1, 2014

Primary Completion (Actual)

December 1, 2016

Study Completion (Actual)

July 1, 2017

Study Registration Dates

First Submitted

January 9, 2014

First Submitted That Met QC Criteria

January 9, 2014

First Posted (Estimate)

January 10, 2014

Study Record Updates

Last Update Posted (Actual)

November 1, 2019

Last Update Submitted That Met QC Criteria

October 30, 2019

Last Verified

October 1, 2019

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Major Depressive Disorder

Clinical Trials on Pramipexole

Subscribe