Characterization of [11C]Flumazenil to Image GABA Transmission in Healthy Adult Subjects and Subjects With Alcohol Dependence
Condition: Alcoholism
MeSH terms: Alcoholism
Study type: Interventional
Phase: Phase 1

Summary: 
      Background:

      - This study is being done to examine the role of a chemical GABA in the brain of alcohol
      dependent patients. GABA is the chief inhibitory neurotransmitter in the central nervous
      system. It helps induce relaxation and sleep and balances the brain by inhibiting
      over-excitation. Several studies have reported that anxiety disorders such as panic attacks,
      seizure disorders, and numerous other conditions including addiction, are all related to low
      GABA activity. Therefore, we will examine differences in GABA levels between healthy controls
      and subjects with alcohol addiction. Studies such as this are important to the understanding
      of the role of GABA in alcohol addiction.
    

Detailed description: 
      Objectives:

      - By comparing the two PET scans (before and after tiagabine) done in the same day, we can
      understand more about how much GABA your brain makes and about the activity of your GABA
      receptors in the brain.

      Eligibility:

      - Individuals 18-45 years of age who are heavy drinkers or healthy controls.

      Design:

        -  Procedures to determine if you are eligible to take part in a research study are called
           "screening procedures". This will require you to come to the investigators office for
           approximately ½ day. For this research study, the screening procedures include
           comprehensive psychiatric and medical evaluations. Participants be asked to abstain from
           drugs and alcohol for the duration of the study and will be required to make trips
           several times a week for two weeks to provide clean urine samples.

        -  During one of the visits prior to the PET scans, participants will have a magnetic
           resonance image (MRI) taken of their brain.

        -  We will be using a technology called Positron Emission Tomography (PET), which is a
           method used to take pictures of the body, in this case, the brain. We will be injecting
           you with a radiotracer called [11C]flumazenil. A radiotracer is a small amount of a drug
           with radioactivity attached. Because the radiotracer temporarily sticks to the GABA
           receptors in the brain, the PET scan can then measure the activity at GABA receptors by
           measuring the amount of the radiotracer. You will undergo two PET scans with
           [11C]flumazenil on one day for this study. After the first PET scan, you will be given
           an oral dose of tiagabine (Gabitril®), which is a medication approved for the treatment
           of seizure disorder. Tiagabine raises levels of GABA in the brain. It is used in this
           study so that we can measure the changes in GABA levels. Blood samples will be drawn
           during the PET scans.
    

Intervention name(s): [11C]flumazenil; Tiagabine
Intervention type(s): Radiation; Drug
Intervention description(s): [11C]flumazenil is a radiotracer used to measure levels of the neurotransmitter GABA in the human brain.; Tiagabine raises levels of GABA in the brain. It is used in this study so that we can measure the changes in GABA levels.
Intervention MeSH terms: Tiagabine; Flumazenil
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Basic Science