Light and Electron Microscopy of the European Beaver (Castor fiber) Stomach Reveal Unique Morphological Features with Possible General Biological Significance

摘要: Anatomical, histological, and ultrastructural studies of the European beaver stomach revealed several unique morphological features. The prominent attribute its gross morphology was cardiogastric gland (CGG), located near oesophageal entrance. Light microscopy showed that CGG formed by invaginations mucosa into submucosa, which contained densely packed proper gastric glands comprised primarily parietal chief cells. Mucous neck cells represented <0.1% in 22–32% lining lumen. These data suggest develop from undifferentiated migrate through rather than mucous Classical cell formation (i.e., arising cells) occurred lumen, however. muscularis around consisted skeletal muscle tissue. cardiac region rudimentary while fundus/corpus pyloric regions were equally developed. Another unusual feature presence specific mucus with a thickness up to 950 µm (in frozen, unfixed sections) coated mucosa. Our observations this is complex includes secretory granule accumulation cytoplasm pit cells, aggregation inside incorporation degenerating mucus.