Mucous and oxynticopeptic cells in the gastric mucosa of the seps,
Chalcides chalcides (Linnaeus, 1758) were
examined by standard histochemical staining methods and by lectin histochemistry.
The epithelial mucous
cells lining the surface of the stomach and the mucous cells of the fundic
glands elaborated mainly neutral
glycoproteins with β(1,4)GlcNAc oligomers, GalNAc glycosidic residues
and Galβ1,3GalNAc terminal
sequences. The mucous cells of the fundic glands were stained specifically
with the Paradoxical Con A
method. The mucosecreting cells of the pyloric glands produced neutral
glycoproteins, with β(1,4)GlcNAc
oligomers, GalNAc residues and Galβ1,3GalNAc terminal sequences. Terminal
L-fucose bound to the
penultimate GlcNAc residues, and/or difucosylated oligosaccharides
were also present. The pyloric glands
did not stain with the Paradoxical Con A procedure. The morphology of the
oxynticopeptic cells changes
from the oral to the aboral region of the fundic mucosa. In the oral fundic
tract the oxynticopeptic cells
showed cytoplasm filled with zymogen granules, while in the aboral fundic
region these cells contained few
zymogen granules and showed cytoplasm full of empty vesicles, typical of
the acid secreting cells. A
secretion gradient of proteolytic enzymes and hydrochloric acid along the
fundic mucosa of the seps can be
hypothesised.