Microvascular endothelium--a major target for alcohol injury of the human gastric mucosa. Histochemical and ultrastructural study.

In healthy volunteers, we studied the effect in intragastric administration of 100 ml 40% alcohol or isotonic saline on the ultrastructure of gastric oxyntic mucosa with emphasis on gastric mucosal microvasculature. We found that a single dose of 40% alcohol produces exfoliation of the surface epithelium, damage to the mucosal microvessels, extravasation of red blood cells and plasma from disrupted microvessels, and extensive edema of superficial lamina propria. The ultrastructural changes were seen as early as 5 min after alcohol administration and occurred in the mucosal areas where glandular cells did not show necrotic changes. Alcohol-induced injury was localized predominantly to interfoveolar mucosal areas and only occasionally extended to the neck areas. This study demonstrates that the mucosal microvasculature is a primary target for alcohol-induced injury of the human gastric mucosa.