Investigation of the vasodilator and antisecretory role of prostaglandins in the rat gastric mucosa by use of non-steroidal anti-inflammatory drugs.

1 The effects of non-steroidal anti-inflammatory drugs on gastric acid secretion and mucosal blood flow were studied in the rat. 2 Indomethacin, in ulcerogenic doses, caused a dose-dependent rise in pentagastrin-stimulated acid secretion, but decreased mucosal blood flow per unit acid secretion. 3 During resting conditions, indomethacin had no significant effect on acid output, but reduced mucosal blood flow. 4 Pretreatment with indomethacin, phenylbutazone or meclofenamate potentiated the secretory response to dibutyryl cyclic adenosine 3',5'-monophosphate. 5 Indomethacin markedly reduced the mucosal prostaglandin-like activity at a time when mucosal erosion formation had reached steady levels. 6 These results provide evidence that prostaglandins have a local role in the regulation of blood flow and acid secretion in the rat gastric mucosa, and suggest that non-steroidal anti-inflammatory drugs cause mucosal erosions by disrupting these processes.