Electron microscopic findings of polyglucose reacting with iodine

The reaction product of iodine and native glycogen or polyglucose synthesized histochemically by glycogen synthetase or phosphorylase with branching enzyme was studied in the paraboloid of the chick retina by light and electron microscopy. Native glycogen in the paraboloid stained brown, while histochemically synthesized polyglucose stained brown or purple. Electron microscopy revealed that the paraboloid in all experimental groups appeared to have many vacant spaces at the sites of polyglucose particles, as after the amylase digestion test. Native and histochemically synthesized polyglucose particles themselves looked like fine granules or appeared to have various densities in electron micrographs. These findings suggest that native or histochemically synthesized polyglucose particles are partly masked by the iodine atoms involved in the amylase channel in electron micrographs.