In Vivo Nuclear Magnetic Resonance Imaging and Spectroscopic Investigations of Structure and Function of Rodent Brain
30 Jul 2008 | Online Presentations | Contributor(s): Anant B. Patel
Nuclear Magnetic Resonance Imaging (MRI) is a powerful and a versatile imaging modality for non-invasive characterization of host structure and function. MRI has grown in many directions such as functional MRI, diffusion tensor imaging, chemical shift imaging, which is used to detect single cells and cell trafficking, subtle abnormalities in variety of diseases, to understand the mechanism of sensory and cognitive function in human brain. Nuclear Magnetic Resonance Spectroscopy (MRS) is another dimension of MRI, which permits quantitative and non-invasive measurement of metabolites in vivo from a given system. In vivo NMR spectroscopy in combination with the infusion of 13C-labeled substrates has provided important insights into metabolic pathways of different organs. 13C NMR spectroscopy has been used extensively to study neurotransmitter metabolism in rodent and human brain. We have developed a method to determine the contribution of g-aminobutyric acid (GABA) to neurotransmitter cycling and glucose oxidation by using 13C NMR spectroscopy together with infusion of [1,6-13C2]glucose and/or [2-13C]acetate. Using this approach we found that GABA contributes a significant fraction to total neurotransmitter cycling and neuronal glucose oxidation. This presentation will describe the measurement of metabolic rates using in vivo 13C NMR spectroscopy and MRI applications to visualize cells and their tracking in vivo.