Three-dimensional Dynamics of the Golgi Apparatus of Parotid Acinar Cells as Analyzed by Computer Graphics of Cytochemically-marked Serial Sections.

Abstract

To correlate the structure and function of the Golgi apparatus, we employed computergenerated three-dimensional reconstruction from electron micrographs of serial sections treated for thiamine pyrophosphatase (TPPase) cytochemistry. Three-dimensional analyses were conducted for rat parotid acinar cells in a resting state, in the course of mitotic division, and during postnatal development.In resting acinar cells, the TPPase-positive trans elements are the same size as the TPPase-negative middle/cis elements horizontally, and they mutually overlap from side to side. During the mitotic stage, TPPase activity disappears from the disorganized Golgi apparatus and no secretory granule formation is observed. Recovery of the stacked structure and TPPase activity take place in daughter cells at the telophase, which are followed by secretory granule formation. During the differentiation of Golgi apparatus in postnatally developing acinar cells, TPPase activity is expressed following formation of the stacked structure, and then granule formation is initiated. These results clearly demonstrate the close relationship among the stacked structure, TPPase activity and the exocrine function of the Golgi apparatus.