A Mucosal Bleeding Mechanism in the Upper Part of the Gastrointestinal Tract

Abstract

Summary Seven experiments were performed to establish the correlation between mucosal hemorrhages in the gastrointestinal tract and degranulation of mucosal mast cells under the influence of stress and hormonal factors. Stress caused numerous mucosal hemorrhages in the stomach and partial degranulation of the mucosal mast cells in both heparinized and nonheparinized mice. No mucosal hemorrhages ensued in rats after the long term administration of adrenocorticotrophin, cortisone, dexamethasone, and growth hormone. A high incidence of hemorrhages was produced in the gastric mucosa of the rat with histamine and insulin. Mucosal mast cells were degranulated during the short observation period, more in the test animals with hemorrhages in the gastric mucosa than in the animals with no hemorrhages. ACTH and glucocorticoids degranulated the mast cells of the gastric mucosa; growth hormone increased their count and granulation. Large doses of glucocorticoids over a short period caused some mucosal hemorrhages. Growth hormone seemed to inhibit the hemorrhagic effect of glucocorticoids on the gastric mucosa. It is suggested that degranulation of mast cells during stress and various stimulations in the lamina propria of stomach results in local histaminemia and heparinemia leading to vasodilation, mucosal microlesions, and hemorrhages.