Title
In vivo imaging of inhibitory, GABAergic neurons by MRI.
Abstract
The unambiguous detection of specific neuronal subtypes is up to now only possible with invasive techniques or optical imaging after genetic modification. High field magnetic resonance imaging (MRI) has the ability to visualize the brain structure and anatomy noninvasively, with high resolution — but missing the cell specific and functional information. Here we present a new tool for neuroimaging with MRI, enabling the selective detection of GABAergic neurons under in vivo conditions. The specific imaging contrast is achieved by a novel paramagnetic contrast agent, which responds to the activity of the enzyme glutamic acid decarboxylase — expressed solely by inhibitory neurons. The relaxivity of the complex is increased upon decarboxylation of two glutamic acid moieties, thus allowing increased water access to the inner and outer coordination spheres of the paramagnetic ion. The mechanism and specificity of activation were proven with tissue lysates and further applied to a differentiation protocol for murine embryonic stem cells. The relaxation enhancement was studied quantitatively and revealed decreased longitudinal relaxation times in the inhibitory neuron samples compared to the naïve stem cells in vitro and in vivo. Furthermore, this approach offers not only the discrimination of inhibitory, GABAergic neurons in the brain but also may expand the usefulness of MRI for functional imaging on a cellular level.
Year
DOI
Venue
2012
10.1016/j.neuroimage.2012.05.029
NeuroImage
Keywords
Field
DocType
Responsive MRI contrast agent,Stem cell differentiation protocol for GABAergic neurons,Glutamic acid decarboxylase,In vivo MRI of GABAergic neurons
Glutamate decarboxylase,Neuroscience,GABAergic,Stem cell,Biophysics,Psychology,Cognitive psychology,In vivo,Inhibitory postsynaptic potential,Neuron,Preclinical imaging,Magnetic resonance imaging
Journal
Volume
Issue
ISSN
62
3
1053-8119
Citations 
PageRank 
References 
0
0.34
2
Authors
8
Name
Order
Citations
PageRank
Markus Aswendt121.04
Eliana Gianolio200.34
Giorgio Pariani300.34
Roberta Napolitano400.34
Franco Fedeli500.34
Uwe Himmelreich61029.60
Silvio Aime700.68
M Hoehn8999.96