Effects of Hypotonic Stress and Ouabain on Apparent Diffusion Coefficient at Cellular and Tissue Levels.

Ileana Ozana Jelescu¹, Luisa Ciobanu¹, Franoise Geffroy¹, Denis Le Bihan¹

The mechanism causing apparent diffusion coefficient (ADC) decrease in brain tissue with ischemia is not yet clearly established. We evaluated ADC evolution at 17.2T, in isolated Aplysia californica neurons and within tissue (ganglia), following hypotonic shock or exposure to ouabain. Both types of stress caused an increase in ADC in single cells, and an overall decrease in ADC in the ganglia. Cell swelling was readily measurable with hypotonicity, but less obvious with ouabain. These results do not favor the extension of intracellular space as the origin of the observed ADC decrease at tissue level.