Direct demonstration of spatial water distribution in the sponge Suberites domuncula by in vivo NMR imaging

Abstract

Until now, direct, non-invasive in vivo studies on water and metabolite distribution in living sponges have not been possible. Here we apply for the first time the noninvasive technique of nuclear magnetic resonance (NMR) imaging to determine the spatial distribution of water in the marine sponge Suberites domuncula. After transfer of the sponge into deuterated water (D2O) for a short incubation period of 18 min, no significant water exchange was observed, neither in S. domuncula nor in the hermit crab living in symbiosis with it, suggesting D2O to be an ideal contrast enhancing agent for NMR imaging of sponges. Thus, NMR imaging provides a promising technique for the detection (and possibly quantification) of the distribution and transport of water both by diffusion and active transport in a living sponge.