Fig. 4

Ultrastructural analysis of antropyloric tumor cells of TFF1 null mice. Electron micrographs of (A) pre-pit cell cut through apex and base (respectively seen at the top and bottom) and attached to two neighbor cells partially seen on the sides. The cell is characterized by an euchromatic central nucleus and a prominent supranuclear Golgi apparatus producing homogeneously dense mucous granules. In addition, some secretory granules are also visible at the apical surface (original magnification ×4000). (B) High magnification of the area within the rectangle seen in (A) showing details of apical cytoplasm. Note that in between the Golgi region and the apical secretory granules, the cytoplasm is full of dilated cisternae of rough ER (asterisks). Few mitochondria (m) are scattered (original magnification ×6300). (C) A close up of another gastric epithelial cell showing part of the nucleus seen at the right and dilated cisternae of rough ER. Arrowhead, example of ribosomes of the rough ER. Note the accumulation of dense secretory material (arrow) within the lumen of ER (original magnification ×16,000).