TRADITIONAL POSTER - ismrm

Poster Sessions
2272. The Effect of Peripheral Administration of Monosodium Glutamate on Ionotropic Glutamate
Receptor Signalling in the Mouse Brain in Vivo Shown Through Manganese Enhanced MRI
Mohammed Khair Hankir 1,2 , James R. Parkinson 1 , Stephen R. Bloom 3 , Jimmy David Bell 1
1 Metabolic and Molecular Imaging Group, Imperial College, London, United Kingdom; 2 Investigative Medicine, Imperial College ,
London, United Kingdom; 3 Investigative Medicine, Imperial College, London, United Kingdom
Peripheral administration of monosodium glutamate (MSG) stimulates feeding in rodents. This may be due to the direct activation of glutamate receptors
expressed in the arcuate nucleus (ARC) of the hypothalamus. We have used manganese enhanced MRI (MEMRI) to demonstrate that intraperitoneal
administration of MSG dose dependently increases Mn2+ influx into the ARC and that this can be suppressed with a glutamate receptor subtype specific
receptor antagonist. These results reveal that MEMRI is a sufficiently sensitive tool to detect glutamatergic signalling in vivo with high temporal and spatial
resolution.
2273. Reduced Manganese Enhancement and Flow in the Olfactory Pathway in Mice with Experimental
Neuropsychiatric Lupus Demonstrated by Manganese Enhanced MRI
Tammar Kushnir 1 , Shaye Kivity 2 , Eli Konen 1 , David Manor 1 , Nancy Agmon-Levin 2 , Miri Blank 2 , Joab
Chapman 3 , Yehuda Shoenfeld 2 , Galia Tsarfaty 1
1 Dept. of Diagnostic Imaging, MRI Unit, The Chaim Sheba Medical Center, Tel Hashomer, Israel; 2 Center of Autoimmune Diseases,
The Chaim Sheba Medical Center, Tel Hashomer, Israel; 3 Dept. of neurology, Sagol Neuroscience Center, The Chaim Sheba Medical
Center, Tel Hashomer, Israel
Manganese enhanced MRI (MEMRI) allows in-vivo mapping of functional neuronal connections in the brain. The method was used to investigate the
olfactory system in mice with experimental neuropsychiatric lupus (NPSLE), induced by intra-cerebro-ventricular injection of anti-ribosomal-P antibodies.
MEMRI scans were performed before and 40 hours after intranasal MnCl2 administration. NPSLE induction resulted in a depression-like behavior
accompanied with a significant deficit in olfactory function. MEMRI demonstrated impaired olfactory neuronal function expressed as a significant reduction
in normalized manganese enhancement and flow throughout of the olfactory pathway, compared to healthy mice. Our results propose that autoimmune-CNS
conditions may influence olfactory function.
2274. Oral Manganese as an MRI Contrast Agent for the Detection of Nociceptive Activity
Kathleen Elizabeth Jacobs 1 , Deepak Behera 1 , Garry Gold 1 , Michael Moseley 1 , Jarrett Rosenberg 1 , David
Yeomans 2 , Sandip Biswal 1
1 Radiology, Stanford University, Stanford, CA, United States; 2 Anesthesia, Stanford University, Stanford, CA, United States
Manganese-enhanced magnetic resonance imaging (MEMRI) is a potentially powerful diagnostic method for identifying neural regions of pain processing
for image-guided interventions. Manganese can enter nerves via voltage-gated calcium channels, which are selectively upregulated in pain. We gave
manganese by oral gavage to two rat groups: one with spared injury of their sciatic nerves and a sham-operated group. We found that rats with spared nerve
injury have increased manganese ion uptake and retention in their nerves compared to the nerves of sham-operated rats as shown by increased MR signal and
nerve concentrations. Therefore, manganese can specifically enhance nerves associated with nociception.
MRI of Neural Plasticity
Hall B Thursday 13:30-15:30
2275. In Vivo Detection of Axonal Plasticity in Rat Hippocampus Using DTI
Teemu Laitinen 1 , Alejandra Sierra 1 , Asla Pitkänen 1 , Olli Gröhn 1
1 A.I. Virtanen Institute for Molecular Sciences, University of Kuopio, Kuopio, Finland
The ability of in vivo diffusion tensor imaging to detect axonal plasticity in dentate gyrus sub region of hippocampus was studied in rats after kainic acid
induced status epilepticus. Our results show that fractional anisotropy of dorsal dentate gurys is increased 17 months after the brain injury when compared to
healthy control animals. Histological evaluation showed significant increase in the density of mossy fiber sprouting and myelinated axons the kainic acid
treated animals, consistent with the DTI results. The results of this study suggest that axonal plasticity can be detected using in vivo DTI.
2276. Short-Term Learning Induced Plasticity Visualized with Diffusion MRI
shimrit Tzur-Moryosef 1 , tamar Blumenfeld-Katzir 2
1 tel aviv university, tel aviv, Israel; 2 neurobiology, tel aviv university, tel aviv, Israel
Plasticity in the adult brain following learning procedure is commonly attributed to functional plasticity and restricted to the hippocampus. This study we
utilize Magnetic diffusion tensor imaging (DTI) in order to characterize microstructural plasticity induced by short-term learning paradigm. Analyses were
done by ADC and FA parameters in order to characterize both white and gray matter changes. Rats were scanned before and one day after a one-day version
of the Morris water maze task. Paired t-test comparisons demonstrate FA increase in the cingulum bundle and FA and ADC decrease in striatum-related gray
matter, motor and sesorimotor cortex.