Ultrastructure of the cardiac and pyloric glands of the gastric mucosa of the South African hedgehog, Atelerix frontalis

Abstract

The cardiac and pyloric glands in the gastric mucosa of the South African hedgehog, Atelerix frontalis, are described. The cardiac area of the stomach contains proper cardiac glands and lacks undifferentiated fundic glands. The cardiac glands are simple tubular, coiled, and lined with columnar cells ultrastructurally similar to those of the gastric surface epithelium. Secretory granules with varying electron densities fill the apical cytoplasm of these cells. In contrast to other mammals, these glands lack mucous neck cells. The neck of the pyloric glands contains only a single cell type, whereas the basal regions of these glands contain "light" and "dark" cells. The secretory granules in the "dark" cells and the pyloric neck cells have a moderate electron density and often contain an electron dense core. An electron-lucent cytoplasm with numerous polysomes is characteristic of the "light" cells. Some "light" cells contain electron-dense granules in the apical cytoplasm. The presence of only neutral mucins in the cardiac gland cells denotes the absence of mucous neck cells. The acidic mucins within the pyloric neck cells seem to indicate that these cells are mucous neck cells, whereas the neutral mucins within the basally located pyloric gland cells show at least a partial functional difference from the pyloric neck cells. © 1993 Wiley-Liss, Inc.

Histomorphology of the Proventriculus of three Species of Australian Passerines: Lichmera indistincta, Zosterops lateralis and Poephila guttata

“…The mucin produced by these cells forms a gel over the epithelial surface. This mucin has numerous functions such as a lubricant and protective barrier to physical damage by the luminal contents, guards against bacterial invasion (Neutra and Forstner, 1987), regulates epithelial hydration (Lukie, 1977), interacts with secretory immunoglobulin A to produce antibody and antitoxin effects (Kemper and Specian, 1991), and provides a diffusion barrier for nutrients and other small molecules (Gregorowski et al., 1993).…”