Gastric mucosal resistance to a repeated ethanol insult.

The luminal gastric mucosa of anesthetised rats was uniformly exposed to 70% ethanol for 30-45 seconds. Ninety-six per cent of the superficial epithelium was immediately destroyed. The mucosa was allowed to heal for 60 minutes, during which time 85% of the superficial mucosa had re-epithelialised. A thick gelatinous layer of necrotic cells and mucosal exudate formed over the restituted epithelium. To determine whether the mucosa could withstand a second ethanol insult, the same stomachs were re-exposed to 70% ethanol for 30-45 seconds and fixed for quantitative light microscopy. Significant damage to the newly formed epithelium was observed only when the gelatinous layer was first removed and then followed by a second ethanol insult. This resulted in uniform superficial damage to 92% of the mucosal surface with accompanying vascular stasis.