Cell culture of rat gastric fundic mucosa.

The purpose of this study was to develop a primary cell culture system of rat gastric fundic epithelial cells. The cells, isolated enzymatically, were cultured in Coon's modified Ham's F-12 medium supplemented with 10% fetal bovine serum, 15 mM HEPES buffer, fibronectin, and antibiotics. The inoculated cells started to grow rapidly on day 1 (doubling time, 26 h). The cells reached confluency on day 3. On phase contrast microscopy, over 90% of cells possessed epithelial characteristics. Histochemical studies showed (a) 90% of the epithelial cells contained PAS positive granules, (b) 5% of the cells gave a strong reaction for succinic dehydrogenase activity (presumably parietal cells), and (c) immunohistochemical localization of pepsinogen was negative. Ultrastructurally, microvilluslike structures, junctional complexes, Golgi apparatus, mitochondria, rough-surfaced endoplasmic reticulum, and mucous granules were observed. Mitotic figures were clearly observed on Giemsa staining and the mitotic index was maximum on day 2. Autoradiographic and biochemical studies showed these cells possessed the capability to synthesize deoxyribonucleic acid and this ability was maximum on day 2. These cells were able to synthesize and to secrete glycoprotein and this function was significantly increased by 16,16-dimethyl prostaglandin E2. Cyclic adenosine monophosphate produced by the cultured cells was enhanced by addition of 16,16-dimethyl prostaglandin E2 (p less than 0.01). This in vitro system provides a valuable model for studies of cellular functions of gastric mucosa.