Laparotomy stimulates an endogenous gastric mucosal protective mechanism in the rat. A microcirculatory and morphologic study of ethanol injury.
In vivo microscopy in the anesthetized rat unexpectedly revealed that the topical application of 75% ethanol to the gastric mucosa had no effect on the mucosal microcirculation. If, however, the synthesis of endogenous prostaglandin was inhibited by indomethacin, the topical application of 75% ethanol resulted in complete superficial mucosal microcirculatory stasis in the majority of rats. In indomethacin-pretreated rats, Rioprostil, a synthetic prostaglandin E1 analogue, reversed this effect of topical ethanol. The degree of ethanol-induced histologic gastric mucosal damage was inversely correlated with time to complete stasis. Ethanol injury studies under various conditions revealed that laparotomy stimulated a gastric protective mechanism that persisted for between 1 and 2 h and that was blocked by indomethacin. In conclusion, (a) laparotomy stimulates a gastric mucosal protective mechanism that probably is mediated by prostaglandin synthesis, and (b) cessation of mucosal blood flow appears to be an important early step in ethanol-induced gastric mucosal injury, and maintenance of mucosal blood flow by endogenous or exogenous prostaglandin may play a major role in prostaglandin protection.
D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D000431:Ethanol / Q000633:toxicity*; D005753:Gastric Mucosa / Q000098:blood supply / Q000187:drug effects* / Q000473:pathology; D007213:Indomethacin / Q000494:pharmacology; D007813:Laparotomy; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000473:pathology; D011448:Prostaglandin Antagonists / Q000494:pharmacology; D011453:Prostaglandins / Q000502:physiology; D011458:Prostaglandins E / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D016630:Rioprostil
D011448:Prostaglandin Antagonists; D011453:Prostaglandins; D011458:Prostaglandins E; D000431:Ethanol; D016630:Rioprostil; D007213:Indomethacin