Mohammed Khair Hankir1,2, James R. Parkinson1, Stephen R. Bloom3, Jimmy David Bell1
1Metabolic and Molecular Imaging Group, Imperial College, London, United Kingdom; 2Investigative Medicine, Imperial College , London, United Kingdom; 3Investigative 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.