Nutrient storage cells isolation from mantle tissue of Mytilus galloprovincialis: glucose release and glycogen...

A method for obtaining isolated mantle nutrient storage cells and purifying vesicular (VC) and adipogranular (ADG) cells from mantle tissue of Mytilus galloprovincialis is reported. Tissue digestion is partly mechanical (stirring) and partly enzymatic (collagenase + dispase). Purification is carried out through continuous and discontinuous Percoll gradients. VC appears in fraction 3 (d = 1.05-1.08 g/ml) and ADG in fraction 2 (d = 1.09 g/ml). Intracellular glycogen and free-glucose content in September-April period is studied. When glycogen is detectable it is always accompanied by intracellular free-glucose pool in a concentration relationship glycogen/glucose 10:1. Furthermore, a glucose releasing activity elicited by the Ca2(+)-ionophore A23187 was found in isolated cells, which reproduce the former behaviour found with mantle tissue fragments in our laboratory.