Imaging mGluR5 and synaptic density in psychiatric disorders
- Study HIC#:2000020186
- Last Updated:07/15/2021
You are invited to take part in a research study designed to look at the involvement of the glutamate system and neuronal density in mood and anxiety disorders. By agreeing to participate in this research, you may be asked to undergo one or more MRI or fMRI sessions, one or more PET scans, and up to two MRS scans.
- Age18 years - 80 years
- Start Date01/11/2017
- End Date01/31/2018
Trial Purpose and Description
Aim 1: To determine mGluR5 availability in individuals with mood disorders compared to healthy controls as measured with PET brain imaging using [18F]FPEB.
Hypothesis 1: We hypothesize a decrease in mGluR5 availability in individuals with mood disorders in regions responsible for emotional and cognitive processes, including the amygdala, hippocampus, thalamus, anterior cingulate, and frontal cortices.
Aim 2: To determine if glutamate cycling in individuals with mood disorders is altered as compared to healthy controls as measured with [1H]MRS and [13C]MRS.
Hypothesis 2: We hypothesize an increase in glutamate number in individuals with mood disorders as compared to controls.
Aim 3: To determine if the PET alterations in the glutamatergic system of depressed individuals are associated with cognitive deficits observed in depression, including concentration, attention, and memory.
Hypothesis 3: We hypothesize a positive relationship between mGluR5 availability and cognitive functioning, such that individuals with higher receptor availability will perform better on tests of concentration, attention, and memory than individuals with lower receptor availability.
Aim 4: To examine whether changes in mGluR5 availability are dependent on state, or whether the lower availability is due to trait.
Hypothesis 4: Due to changes in endogenous GLU shown with MRS studies, we hypothesize normalization (or increase) in mGluR5 availability in euthymia as compared to depressed state.
Aim 5: To examine synaptic density changes associated with mood disorders using [11C]UCB-J.
Hypothesis 5: We hypothesize lower synaptic density in individuals with MDD and BD, and associations between synaptic density changes and mood severity. We also hypothesize there might be a relationship between synaptic density and mGluR5 availability.
Medically healthy individuals, ages 18-80, with a diagnosis of major depressive disorder (MDD) or bipolar disorder. We also accept healthy controls.