Ergastoplasm
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Ergastoplasm
Cells that biosynthesize and export large amounts of proteins have strongly basophilic cytoplasmic regions, which have been named ergastoplasm (from Greek: ergasticos = industrious,working cytoplasm). In light microscopic images, this basophilic material appears in a variety of forms. The homogeneous or banded material (chromophilic substance) from the basal part of highly active secretory gland cells (see Fig.19) is very well known, and so are the smaller or larger chromophilic bodies in the cytoplasm of nerve cells to their ribosome content, these cell components have a high affinity for basic dyes (e.g., hematoxylin). Electron microscopy reveals an elaborate system of densely packed granular endoplasmic reticulum (rough ER, rER) as the material that makes up the basophilic ergastoplasm seen in light microscopy. This figure shows acini from the exocrine pancreas. These cells show pronounced basal basophilia 1 . In contrast, the supranuclear and apical cytoplasmic regions are only sparsely granulated. 1 Cell regions with ergastoplasm, basal basophilia 2 Lumina of the acini 3 Blood vessels
Basophilic cytoplasm (blue) in the basal regions of gland cells (basal basophilia) 1 (cf. Fig.18). The presence of ribosomes accounts for the affinity to basic dyes. The basophilic cytoplasm corresponds to the granular (rough) endoplasmic reticulum (rER).The supranuclear and apical cell regions contain no ergastoplasm and therefore remain unstained. The round cell nuclei in the basal cytoplasmic region are stained light blue. Parotid gland (glandula parotidea) of the rat. 1 Cell regions with ergastoplasm, basal basophilia 2 Acini 3 Blood vessels
The cytoplasm of multipolar neurons fromthe columna anterior of the spinal cord contains a dense distribution of fine or coarse bodies, which can be emphasized by staining with cresyl violet. They are called Nissl bodies or Nissl substance (tigroid bodies), after Franz Nissl (1860–1919), who discovered them. Electron microscopy identifies groups of polysomes and components of the rough (granular) endoplasmic reticulum (ergastoplasm ) as the structures that correspond to the Nissl bodies.
1 Nissl bodies (substance) 2 Nucleus with nucleoli 3 Dendrites 4 Glial cell nuclei
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