Ultrastructural demonstration of glucose 6-phosphatase in cerebral cortex

A two-stage fixation technique has been developed to obtain morphological preservation and retention of glucose 6-phosphatase (G6-Pase) activity for its demonstration in rat cerebral cortex. The technique was then employed to localize the enzyme in the cortex where it produced a dense reaction over the well developed granular endoplasmic reticulum cisternae in nerve cells and oligodendrocytes which contrasted with a thin reaction in astrocytes. Other membranous organelles showed no reaction.