Frog Gastric Tubular Cells: Isolation, Culture, and Some Properties

Abstract

We have isolated and maintained primary cultures of tubular cells from the gastric mucosae of the frog Rana catesbeiana. During the first few days after isolation and culture, cell surface damage was manifested by enhanced leakage of intracellular pepsinogen and a lack of response to known gastric secretagogues with respect to pepsinogen release and respiration. After several days in culture, the cellular pepsinogen levels increased slightly but significantly and the spontaneous loss of pepsinogen from the cells showed a marked decline, indicating repair of the initial membrane or surface damage. The intact cells possessed p -nitrophenylphosphatase activity. After several days in culture, the respiratory activity became sensitive to the serum concentrations of the culture medium and was relatively stable. Antibiotics used in establishing primary cultures reversibly inhibited respiration and pepsinogen synthesis. A variable response to the gastric secretagogues was observed with regard to respiratory and pepsinogen secretory activities, whereas the p -nitrophenylphosphatase activity remained unaffected. There was no indication that the cells divided under the present culture conditions. Although these cells did not attach firmly to the surface of plastic or glass culture flasks, preliminary evidence indicates that collagen gel may provide an appropriate matrix for cell attachment and permit further studies with a reconstituted epithelium comprised of a homogeneous gastric tubular cell population.