Meeting Banner
Abstract #4382

Transport Mechanisms of Intracellular Metabolites in the Brain: New Insights by Diffusion-Weighted NMR Spectroscopy with Oscillating Gradients

SUMMA25Charlotte Marchadour1, 2, Vincent Lebon1, 2, Julien Valette1, 2

1CEA-MIRCen, Fontenay-aux-Roses, France; 2CEA-CNRS URA 2210, Fontenay-aux-Roses, France

Transport of molecules within cells is a key process that can be achieved either passively by random diffusion, or by active transport (e.g. cytoplasmic streaming). The relative contribution of passive and active transport mechanisms to the ADC of intracellular metabolites and intracellular water is still debated. We investigate metabolite motion in the rat brain using diffusion-weighted spectroscopy with oscillating gradients. The dependence of metabolite ADC on the diffusion frequency is observed for the first time, making random diffusion emerge as the dominant transport mechanism. Subsequent data modeling further rules out the plausibility of significant active transport.

Keywords

account accounts achieved active adjusted allow another apparent appears approximate attenuation autocorrelation best birdcage body brain cell cells cellular close closer coefficient coil consisted consistency consistent constrained contribution converge corresponds cosine cytoplasm cytoplasmic dependence dependent determined determining diameter diffusion distance domain dominance dominant eddy effective either ensemble equal equipped establishes exclusively extending fact fibers fitted fluid free frequencies frequency function geometrically gradient gradients healthy hindered idea in vivo individual insights integrated integration interpretation intracellular investigate invoked known leaving linear long longer loss lowest makes many measured mechanism mechanisms metabolite metabolites model modeling models modulated molecular molecules moment motion negative numerical organelles oriented original oscillating particular passively plausibility pores posse powerful processes processing quantification radiology random ranging rats reception reinforced reinforces restricted rodent room roses sampling scales scanner scanning session sessions solid spectra spectroscopy spectrum spherical stability streaming stroke summed surface tail theory transform transport trends typical unknown variation varied velocity water waveform yielded