1. Extracts of human stomach homogenized in Krebs solution had more PGE2‐like activity than tissue homogenized in acid/ethanol or in the presence of indomethacin, indicating that the tissue can synthesize PGE2.
2. The distribution and synthesis of PGE2‐like substance in human stomach was determined by extracting frozen sections cut parallel to the mucosal surface. Peak levels usually occurred at a depth of 0–600 μm in the mucosa.
3. Small amounts of a PGE2‐like substance were present in basal gastric juice, and its concentration was usually even lower in secretion stimulated by pentagastrin or histamine.
4. Submaximal acid secretion produced by I.V. infusion of pentagastrin generally fell slightly when indomethacin was administered rectally to inhibit PG synthesis.
5. These experiments, together with the findings that orally administered PGE compounds do not inhibit human gastric acid secretion, seem to argue against a possible inhibitory role for PGE2 in gastric acid secretion in man.
6. If this is so, it would follow that gastric bleeding caused by aspirin‐like drugs is not due to increased acid secretion. A hypothesis is presented that tissue damage following vasoconstriction and ischaemia, due to inhibition of PG synthesis in blood vessels, contributes to the bleeding.
SUMMARY This is the first report of human gastrointestinal arachidonate and prostanoids measured quantitatively by gas chromatography-mass spectrometry (GC-MS) The methods for gas chromatography-mass spectrometry (GC-MS) were as reported previously.' In brief, the dried extract obtained as described above was dissolved in dichloromethane. An aliquot was taken for GC-MS and further purified by LH20 column chromatography; non-polar impurities were eluted with dichloromethane, and the eicosanoids were eluted with methanol which was then evaporated. Deuterated standards were added, and each dried methanol extract was dissolved in doubledistilled water acidified to pH 3 with hydrochloric acid. Each solution was percolated through an Amberlite column which was then washed with distilled water, and the eicosanoids were eluted with 315 on 11 May 2018 by guest. Protected by copyright.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.