Most cells in the gastric epithelium are linked to neighboring cells via tight junctions, as are intestinal epithelial cells. Tight junctions not only seal adjacent cells together, but also separate apical membranes from basolateral membranes. These cell-cell junctions are important as a critical part of the gastrointestinal barrier that shields the body from ingested materials until they can be broken down and absorbed or eliminated. Since the turnover rate of many cells that comprise the gastric epithelium is high, there must be a careful balance between cell death and cell proliferation in order that the integrity of the tissue is preserved. Replenishment of the gastric epithelium is sustained by stem cells located in gastric pits.

This widefield image of a rat stomach tissue section was produced by probing the specimen with Alexa Fluor 568, Oregon Green 488, and Hoechst 33342. The Alexa Fluor dye was conjugated to phalloidin, targeting the cytoskeletal filamentous actin network, and Oregon Green 488 was conjugated to WGA in order to label the Golgi complex. Cell nuclei were visualized with Hoechst 33342. Images were recorded in grayscale with a 12-bit digital camera coupled to a Nikon Eclipse 80i microscope equipped with bandpass emission fluorescence filter optical blocks. During the processing stage, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles.