The stomach is a sac-like organ that in humans exhibits a J-shape and can be considered to be divided into several different sections. The small gastric region adjacent to the esophagus is called the proximal stomach or the cardia. Neighboring this section is the main body of the organ and along the upper part of the body is the fundus. The lower region located next to the small intestine is the distal stomach, which includes the antrum and the pylorus. The pylorus opens into the duodenum, the uppermost region of the intestine.

The sample of rat stomach tissue featured in the digital image above was labeled with Oregon Green 488 conjugated to wheat germ agglutinin, a lectin that selectively binds to sialic acid residues found in both mucoproteins and glycoproteins. The cells were also stained with Alexa Fluor 568 conjugated to phalloidin and the dye Hoechst 33342, which target the cytoskeletal filamentous actin network and nuclear DNA, respectively. 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.