Correlative light and scanning electron-microscopic study of feline gastric mucosa: the cardiac region (pars cardiaca).

The cardiac region (pars cardiaca) of the cat's stomach was examined with light and scanning electron microscopy. The glands are simple, coiled tubular, and contain mucus-secreting cells. Their surfaces are covered with microvilli which are concentrated on the boundaries of the mucus-secreting cells. A few cells interposed between the glandular cells are probably G cells. They are identified by apical projections of long microvilli into the lumen of the gland. The surface epithelial cells lining the cardiac region are covered by minute microvilli. The muscularis mucosae is not distinctly divided into two layers. However, a group of smooth muscle cells which are directed in a circular manner around the gastroesophageal junction is considered to be the distal esophageal sphincter.