The Fine Structure of the Multivesicular Body and Their Relationship to the Ultracellular Constituents of the Central Nervous System*†

Abstract

Recent investigations on the compartmentalization of some biochemical processes (1–2) and the electron microscope differentiation of a variety of ultracellular components suggest that the orderly functioning of the complex and diversified intracellular metabolism might be patterned along fine ultra-structures and carried out by some characteristic organelles (3–5). Among the latter there is an organelle which has attracted the attention of several investigators (6–15). This was designated as “vesicular structure” (6), “membrane-bound” (16), “membrano vesicular body” (14), and, finally, multivesicular body or MVB (7, 8–13,15, etc.). Since the MVB's origin is obscure and its significance is debated, we attempted a systematic study of this organelle in the CNS of controls and in various pathologic conditions in order to explore some of its functional and biological properties.