Effect of compound 48/80 on canine gastric mucosa.

The effect of compound 48/80 on the mucosal barrier of the canine Heidenhain pouch and mast cell content of gastric mucosa has been studied. 48/80 was administered in increasing doses (0.5--2.0 mg/kg) over 5 days. 0.5 mg/kg produced signs of systemic histamine release and stimulation of acid secretion by the pouch; these effects being most marked on the 1st day and absent on the 5th. Subsequent exposure of the mucosa to sodium taurocholate produced damage to the barrier similar to that in untreated animals. Histological examination revealed no evidence of mucosal mast cell degranulation by 48/80. The results suggest that the effects of 48/80 on gastric mucosa are mediated by systemic release of histamine and that local mast cells are resistant to its action.