The cytoplasm of the Schwann cell is rich in organelles. A Golgi apparatus is located near the nucleus, and cisternae of the rough ER occur throughout the cell. Lysosomes, multivesicular bodies, glycogen granules and lipid granules, also termed pi granules, also can be seen. The cell is rich in microtubules and filaments, in contrast to the oligodendrocyte. The plasmalemma frequently shows pinocytic vesicles. Small, round mitochondria are scattered throughout the soma. The nucleus, which stains intensely, is flattened and oriented longitudinally along the nerve fiber. Aggregates of dense heterochromatin are arranged peripherally [3].