Salicylate effects on a monolayer culture of gastric mucous cells from adult rats.

Aspirin, acetyl salicylic acid, damages gastric mucosal cells. This effect is considered related to its inhibition of prostaglandin synthesis. On the other hand, sodium salicylate has been reported to be cytoprotective against drug damage to gastric mucosa in vivo. One reason for this difference is that salicylic acid, unlike acetyl salicylic acid does not inhibit prostaglandin synthesis by gastric mucosa in vivo. Previous studies on tissue culture cells from our laboratory have required gastric mucosa from fetal rats; this was time consuming and expensive. The purpose of this study was to develop a primary cell culture of adult rat fundic epithelial cells and to test the effect of sodium salicylate on: (1) prostaglandin (PGE2) production, (2) cell viability, (3) reducing cell damage by sodium taurocholate. Gastric epithelial cells were isolated from adult rat stomachs and cultured on collagen gel. Cells reached confluency on day 4 at which stage fibroblasts were rarely seen (less than 1%). Autoradiographic study showed that cultured cells incorporated [3-H] thymidine into nuclei. In histochemical studies, 94% of the cells contained PAS positive granules (mucous cells). Mucous granules were observed in the cytoplasm of the majority of cells by electronmicroscopy. These cells synthesised prostaglandin E2 as determined by radioimmunoassay. Indomethacin 10(-4) M strongly suppressed PGE2 production after 30 minutes while 10(-3) and 10(-4)M sodium salicylate had no effect. Pharmacologic concentrations of 10 mM sodium salicylate had no effect on PGE2 production at 30 minutes and only weakly inhibited production after one hour incubation. Sodium salicylate up to 30 mM had no effect on cell viability, a concentration of 50 mM being necessary to produce significant cell damage. Sodium salicylate 10 mM significantly protected cells against damage induced by 10 mM sodium taurocholate. We conclude: (i) adult rat gastric mucous epithelial cells can be successfully cultured in vitro; (ii) prostaglandin synthesis is inhibited by indomethacin but not by low doses of sodium salicylate; (iii) sodium salicylate does not damage gastric mucosal cells except at very high concentrations; (iv) sodium salicylate protects against damage to cells induced by sodium taurocholate.