Ultrastructural morphology of light beta cells in pancreatic tissue implanted into the anterior eye-chamber of rats

The ultrastructure of light beta cells in pancreatic tissue implanted into the anterior eye-chamber of homologous rats was described using electron microscopical method. The light beta cells contain more mitochondria and rough-surfaced endoplasmic reticulum cisternae and dilatated smooth endoplasmic reticuli than the dark beta cells. Their cytoplasm are poorly stained and contain secretory beta granules of similar morphological form to those in the dark cells. The secretory granules are also more heterogenous. The light cells seem to represent the early secretory stages of the beta cells.