Protection of gastric mucosa in rats. Differences between vagotomy, atropine, and PGE2

We have studied the protective effects of truncal vagotomy, atropine, and PGE2 against gastric mucosal injury produced by necrotizing agents (0.2 N NaOH, 0.6 N HCl, absolute ethanol), acetylsalicylic acid (ASA) and HCl, or serotonin (5HT). Vagotomy, atropine, and PGE2 prevent the effects of different noxious agents. Vagotomy is protective only against 5HT and against ASA + 0.15 N or 0.35 N HCl, whereas atropine and PGE2 are also protective against the necrotizing agents. The effectiveness of vagotomy against ASA + 0.35 N HCl does not depend on the inhibition of acid secretion and supports the hypothesis that removal of the vagal drive counteracts the effect of H+ back-diffusion.