Recovery of mucin content in surface layer of rat gastric mucosa after HCl-aspirin-induced mucosal damage.

Quantitative changes in mucin (mucus glycoprotein) in different layers of rat gastric mucosa after mucosal damage induced by acidified acetylsalicylic acid (HCl-aspirin; 0.15N HCl, 20-200 mg acetylsalicylic acid/kg body weight) were studied. More than 50 mg/kg HCl-aspirin led to a significant increase in macroscopic gastric injury (expressed as ulcer index) at 3 h, compared with control (no aspirin) and there was a significant recovery at 7 h. Three h after dosing with 50 mg/kg acidified aspirin, there was superficial mucosal damage and decreased mucin content in the surface mucosal layer. Mucin production recovered 7 h after the administration of 50 mg/kg acidified aspirin. Doses of acidified aspirin higher than 100 mg/kg decreased mucin content in the surface and deep corpus mucosal layers and no recovery was seen 7 h after the administration. Physiological damage after the administration of 50 mg/kg HCl-aspirin was limited mainly to surface epithelial mucus cells. An experimental model in which superficial erosion was induced in rat gastric mucosa was established with low-dose HCl-aspirin.