Experimental evidence for cytoprotective effect of atropine on the rat gastric mucosa.

The inhibitory effect of atropine on the gastric mucosal damage produced by topical aspirin has been studied in the rat, in the presence and in the absence of intragastrically applied 160 mmole/l HCl. The gastric mucosal damage was produced by aspirin given intragastrically in doses of 192 mg/kg. The topical application was done alone or in the presence of 160 mmole/l HCl. The ulcer incidence, the number and size of gastric mucosal damage were studied during 4 h. The aspirin solutions were administered with or without atropine (in doses of 4 and 10 mg/kg). The atropine was added immediately after the administration of aspirin. The results were as follows 1. A dose-dependent inhibition of ulcer incidence, number and size of gastric mucosal damage was produced by atropine in both groups of animals, when the aspirin was given alone or together with 160 mmole/l HCl; 2. The inhibitory effect of atropine was significantly weaker in the group treated with aspirin plus 160 mmole/l HCl than in th aspirin-treated group. It has been concluded the ulcer-preventing effect of atropine is mediated partly through the inhibition of gastric H+ secretion, and partly some "cytoprotective effect"; the extent of the "cytoprotective effect" of atropine was about half that on gastric H+ secretion.