Mucus, gastrin and somatostatin cells in cultured rat antral mucosa: immunofluorescence, ultrastructural and radioimmunological studies.

Cells were isolated from the gastric antrum of newborn rats (7 and 10 days old) with the intent of studying mucus, gastrin (G), and somatostatin (D) cells. These cells were maintained in culture for 20 days. Their secretory properties were studied in vitro by cytochemical, immunocytochemical and radioimmunological methods. In vitro, mucus cells as well as G and D cells synthesized their secretory products intensely for the first 48 h, but beyond this point, their activity decreased. Mucus cells had a high rate of multiplication and formed sheets of epithelial cells in vitro. Their PAS-positive secretions were synthesized up until the 7th day of culture. During the first 3 days of culture, gastrin cells secreted detectable amounts of the hormone in the culture medium, but afterwards their secretion decreased. Somatostatin cells remained active until at least the 7th day of culture. They displayed long cytoplasmic processes which may serve as a means of communication with neighboring cells. Using ultrastructural techniques, mucus and endocrine cells were found to persist in culture. From a morphological point of view, they appeared similar to the cells found in the original antral tissue and this is an argument for the persistence of the secretory properties in cultivated cells. This experimental model appears to be reproducible and may be useful in the study of secretions of somatostatin, gastrin and mucus in the gastric antrum of the rat.