Glycoprotein synthesis in the mucous cells of the vascularly perfused rat stomach. III. Mucous cells of the antrum and the duodenal glands

Abstract

Labeled leucine, serine, galactose, glucosamine, fucose, and sulfate were administered to rat stomachs in a vascular perfusion system. Sections of gastric fundus and antrum, and of the duodenal glands, were studied by light-microscopic autoradiography. The rate of incorporation of radioactive label in the various mucous cell types of the antrum and of the duodenal glands was measured by counting the silver grains over each cell type and comparing this rate with that of the surface mucous cells of the fundus. The following major observations were made: The patterns of incorporation in the mucous cells on the surface and in the pits of the antrum did not differ essentially from those of the surface mucous cells of the fundus. On the contrary, the incorporation patterns of the surface mucous cells of the fundus differed considerably from those of the mucous cells of the antral glands and from the mucous cells of the duodenal glands. The mucous cells of the antral glands showed a lower incorporation rate of amino acids and of (amino) sugars, especially of galactose and glucosamine, but a higher incorporation rate of sulfate. The mucous cells of the duodenal glands showed a considerably higher rate of incorporation for serine, but a lower rate for glucosamine. No differences were seen for leucine, galactose, and sulfate. The relatively low synthetic activity of the mucous cells of antral glands correlates well with the various amounts of RER, Golgi system, and secretory granules, found in these cells, and with the histochemical staining characteristics of their mucous granules. The mucous cells of the duodenal glands are characterized by typical parallel arrays of their numerous RER cisternae and by a low number of small secretory granules.

Dynamic histology of the antral epithelium in the mouse stomach: II. Ultrastructure and renewal of isthmal cells

“…Finally, the granules of dense granule cells resembled those described by previous authors in pit cells (Leblond and Lee, 1979;9o 8o r,o earlier, this common precursor was taken to 40 Smits and Kramer, 1981) and, therefore, the dense granule cells found mostly in the upper isthmus could be the precursors of pit cells. The granules of the core granule cells of lower isthmus had some similarity with the core granules described in gland cells (Rubin et al, 1968;Krause et al, 1977;Leblond and Lee, 1979;Smits and Kramer, 1981).…”

“…The average diameter of the granules is 278 nm, significantly larger than that of mottled cells (Table 2). Moreover, the granules are similar to, but smaller than, those previously described in gland cells (Rubin et al, 1968;Krause et al, 1977;Leblond and Lee, 1979;Smits and Kramer, 1981). The core granule cells are relatively frequent since they represent about 28% of isthmal cells.…”

“…10, 11). The granules are similar to those that have been described in pit cells (Leblond and Lee, 1979;Smits and Kramer, 1981). Dense granule cells represent about 17% of isthmal cells.…”

“…Moreover, Alcian blue staining indicates the mucus to be neutral in pit cells and acidic in gland cells (Sheahan and Jervis, 1976). In the electron microscope, gland cells show pale granules which include a small electron-dense spot or "core" (Rubin et al, 1968;Krause et al, 1977;Leblond and Lee, 1979;Smits and Kramer, 1981) to which pepsinogen has been localized (Zeitoun et al, 1972). Pit cells, on the other hand, have granules which are generally electron-dense and homogeneous (Leblond and Lee, 1979;Smits and Kramer, 1981).…”

“…In the electron microscope, gland cells show pale granules which include a small electron-dense spot or "core" (Rubin et al, 1968;Krause et al, 1977;Leblond and Lee, 1979;Smits and Kramer, 1981) to which pepsinogen has been localized (Zeitoun et al, 1972). Pit cells, on the other hand, have granules which are generally electron-dense and homogeneous (Leblond and Lee, 1979;Smits and Kramer, 1981). Toward the surface, however, some of these granules may exhibit a core of unknown content (Yeomans, 1974).…”