Neuronal and Astrocytic Metabolites Exhibit Different Diffusion Behavior, as Observed by Diffusion-Weighted Spectroscopy at Ultra-Long Diffusion Times.

Chlo Najac¹, ², Charlotte Marchadour¹, ², Martine Guillermier¹, ², Diane Houitte¹, ², Philippe Hantraye¹, ², Vincent Lebon¹, ², Julien Valette¹, ²

Due to the specific intracellular compartmentation of brain metabolites, diffusion-weighted NMR spectroscopy is a unique tool to explore the intracellular space. In the present study, the dependence of the apparent diffusion coefficient (ADC) on the diffusion time td was measured for five brain metabolites up to ultra-long td (~2 s), in order to explore long-range cell geometry. Our data suggest that metabolites exhibit different behaviors depending on their compartmentation in neurons or astrocytes, probably arising from the different long range geometry (in particular spatial extension) of these two cell types.