Spectroscopic Imaging at 4T: A Drug Challenge Study
Information source: Mclean Hospital
ClinicalTrials.gov processed this data on August 23, 2015 Link to the current ClinicalTrials.gov record.
Condition(s) targeted: AOD Effects and Consequences
Intervention: Alprazolam (Drug); Dextroamphetamine (Drug)
Phase: N/A
Status: Completed
Sponsored by: Mclean Hospital Official(s) and/or principal investigator(s): John E Jensen, Ph.D., Principal Investigator, Affiliation: Mclean Hospital
Summary
An advanced technique for rapid magnetic resonance proton spectroscopic imaging (1H-MRSI)
will be employed in a drug challenge study in healthy volunteers to spatially map and
measure acute changes in the brain chemicals GABA, glutamate and glutamine after
administration of a drug. Three condition will be tested in a double-blind fashion,
i)depressant, ii)stimulant, iii)placebo. It is hypothesized that unique and reproducible
spatial and directional metabolic response patterns will be observed, unique to each
condition within the brain.
Clinical Details
Official title: Spectroscopic Imaging of GABA and Glutamate/Glutamine in Healthy Volunteers at 4T: A Double Blind, Crossover Drug Challenge Study
Study design: Intervention Model: Single Group Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Basic Science
Primary outcome: Magnitude of metabolite level changes throughout the brain with separate administration of Dexedrine and Alprazolam
Secondary outcome: Spatial distribution of metabolite level changes throughout the brain with separate administration of Dexedrine and Alprazolam
Detailed description:
Proton magnetic resonance spectroscopy (1H MRS) is a powerful tool for assessing
neurochemistry non-invasively in vivo. However, the primary shortcoming in most studies is
the lack of spatial coverage afforded by the typical single-voxel design. Limits on
participant tolerance and financial resources restrict single-voxel studies to an
examination of one or two carefully chosen voxels per scan, thus inadequately addressing the
question of focal vs. global pathophysiology. A secondary shortcoming is that most studies
report on either GABA or glutamate-glutamine (Glu-Gln) due to the technically demanding
spectral-editing techniques that must be implemented in order to resolve and quantify those
metabolites with any accuracy.
1H MRS imaging (MRSI) can partially overcome these limitations by providing a global picture
of brain chemistry rather than just the focal snapshot afforded by the single-voxel design.
However, the scan time necessary for collecting enough data for adequate spatial resolution
and signal-to-noise, particularly if also using specialized spectral-editing techniques, is
still too lengthy. We recently developed a method that combines Spectroscopic Imaging with
the MEGAPRESS-based difference-editing acquisition for optimal GABA detection as well as for
optimal detection of Glu and Gln. This MEGACSI sequence will permit us to obtain the
maximum amount of neurochemical information in a clinically sound scan time, while using the
current state-of-the-art MRS editing methods for optimal detection of GABA, Glu, and Gln.
Eligibility
Minimum age: 21 Years.
Maximum age: 45 Years.
Gender(s): Male.
Criteria:
Inclusion Criteria:
- Participants will be male volunteers between the ages of 21-45
- Non-smoking participants are preferred, but will admit those who smoke less than 5
cigarettes per day
- Participants must be able to read screening materials including consent form and give
informed consent
Exclusion Criteria:
- Participants cannot meet DSM-IV criteria for lifetime and/or current mood, anxiety,
psychotic, and alcohol/drug use disorders as identified by the SCID
- Participants cannot be taking any prescription medication (except oral
contraceptives, certain short-term anti-fungal agents, and some topical creams for
dermal conditions) or nutritional supplements
- Participants cannot be taking any psychotropic medications
- Participants cannot have a history of major head trauma resulting in cognitive
impairment, seizure, or other neurological disorders.
- Participants cannot have any conditions that are contraindicated for MRI
- Participants cannot have a family history of alcoholism
- Participants cannot have any abnormal blood chemistries/urinalysis results or any
other medical condition that may affect drug disposition (e. g., Hepatitis C)
- Participants cannot have current or past cardiac problems, and they also cannot have
a family history of sudden death or ventricular arrhythmia
- Participants who, in the investigators' judgment, will not likely be able to comply
with the study protocol.
- Participants cannot have any clinically significant findings in the structural
anatomic brain scans (per the MRI report read by a board-certified radiologist).
Locations and Contacts
McLean Imaging Center, McLean Hospital, Belmont, Massachusetts 02478-9106, United States
Additional Information
Starting date: June 2013
Last updated: March 27, 2014
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