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Dopamine and Insulin Resistance

This study has been completed.
Information provided by (Responsible Party):
Julia P.Dunn,MD, Vanderbilt University Identifier:
First received: December 2, 2008
Last updated: December 12, 2015
Last verified: February 2011
Obese individuals have fewer striatal dopamine type 2 receptors (DRD2) than normal weight individuals. Lower DRD2 levels are associated with addiction and a decreased sense of pleasure.Obesity is also associated with insulin resistance (poor insulin action).We propose that insulin resistance and low DRD2 are associated. Using PET imaging,we aim to determine DRD2 binding potential (BP) in the brain is associated with insulin resistance and neuroendocrine hormone levels. Obese participants will be compared to lean, gender and age similar participants. We also aim to determine the effect of caloric restriction on DRD2 BP in obese subjects

Condition Intervention
Radiation: PET scan
Procedure: Oral glucose tolerance test
Procedure: MRI
Behavioral: Psychological scales to assess attitudes and behaviors related to eating and quality of life
Other: Caloric Restriction

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: Open Label
Official Title: Dopamine and Insulin Resistance

Resource links provided by NLM:

Further study details as provided by Vanderbilt University:

Primary Outcome Measures:
  • Are fasting neuroendocrine hormones and insulin sensitivity associated with DRD2 receptor binding? [ Time Frame: Day of study ]

Secondary Outcome Measures:
  • Are certain eating behaviors associated with DRD2 binding? [ Time Frame: Day of study ]
  • Does caloric restriction alter DRD2 DP in obese participants? [ Time Frame: Day of study ]

Estimated Enrollment: 40
Study Start Date: December 2008
Study Completion Date: December 2012
Primary Completion Date: April 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Obese and lean controls
Obese participants and age and gender similar lean controls
Radiation: PET scan
Subjects will undergo a PET scan of the brain using the radioligand,fallypride [18F]. Obese subjects who complete caloric restriction will have repeat scan after diet.
Procedure: Oral glucose tolerance test
Subjects will be required to drink a glucose solution; blood samples will be taken over a 5-hour time period
Procedure: MRI
An MRI of the brain and abdomen will be performed prior to PET scan
Behavioral: Psychological scales to assess attitudes and behaviors related to eating and quality of life
A series of short psychological scales will be administered during the study.
Other: Caloric Restriction
Obese participants will go a shortterm very low calorie diet


Ages Eligible for Study:   18 Years to 60 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Ages 18-60 yrs
  • obese BMI > 30kg/m2 and Weight less than 350 lbs
  • lean control BMI 18-25kg/m2

Exclusion Criteria:

  • Structured exercise > equivalent to 30mins 5x week of walking times a week
  • History of Substance Abuse, including but exclusive to alcohol, cocaine, marijuana, heroin, nicotine
  • Current psychiatric disorder or significant h/o disorder
  • Use or any antidepressants or antipsychotics for last 3-6months or depot antipsychotics in the last 12 months
  • Any condition felt by PI or co-investigators to interfere with ability to complete the study
  • Inability to abstain from alcohol, physical exercise or > 1 cup of coffee or equivalent daily for 3 days prior to imaging studies
  • Significant co-morbidities including atherosclerotic disease, metabolic disease, liver or renal insufficiency or abnormality found on MRI
  • Any condition which would interfere with MRI or PET studies, e.g. claustrophobia, cochlear implant, metal fragments in eyes, cardiac pacemaker, neural stimulator, tattoos with iron pigment and metallic body inclusions or other metal implanted in the body which may interfere with MRI scanning
  • Subjects on medications determined by PI, ex. sibutramine, frequent benzodiazepines or related drugs, which could affect quality of study for last 3 months.
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Please refer to this study by its identifier: NCT00802204

United States, Tennessee
Vanderbilt University Medical Center
Nashville, Tennessee, United States, 37232
Sponsors and Collaborators
Vanderbilt University
Principal Investigator: Julia P Dunn, MD Vanderbilt University Medical Center
Study Director: Robert M Kessler, MD Vanderbilt University Medical Center
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Julia P.Dunn,MD, Physician, Vanderbilt University Identifier: NCT00802204     History of Changes
Other Study ID Numbers: IRB#080861 and 061246
Study First Received: December 2, 2008
Last Updated: December 12, 2015

Keywords provided by Vanderbilt University:
Insulin Resistance
Neuroendocrine regulation
Eating behaviors
Dopamine signaling

Additional relevant MeSH terms:
Insulin Resistance
Glucose Metabolism Disorders
Metabolic Diseases
Dopamine Agents
Hypoglycemic Agents
Physiological Effects of Drugs
Cardiotonic Agents
Autonomic Agents
Peripheral Nervous System Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Protective Agents processed this record on April 25, 2017