Effect of cepharanthine on neuro-humoral excitatory responses of gastric movement in dog.

In order to clarify the role of histamine in the neuro-humoral excitatory mechanism in the stomach, the effect of cepharanthine (an inhibitory agent of histamine release from mast cells) on excitatory response of gastric movement and increase in gastric mucosal histamine content caused by nerve stimulation (vagus and splanchnic nerves) or administration of tetragastrin were investigated in dogs. The animals were anesthetized with pentobarbital sodium and immobilized with gallamine triethiodide. The following results wee obtained. Increase of gastric mucosal histamine content caused by vagal and splanchnic nerve stimulation and administration of tetragastrin was inhibited by administration of cepharanthine. Cepharanthine inhibited the tonic contraction of the innervated antral pouch or isolated antral circular muscle strip caused by stimulation of vagus nerve. Tonic contraction of the innervated antral pouch caused by electrical stimulation of the splanchnic nerve after nicotinization of celiac and superior mesenteric ganglia was inhibited by administration of cepharanthine. Cepharanthine inhibited motor excitatory response of the denervated corpus pouch caused by stimulation of vagus and splanchnic nerves and by administration of tetragastrin. These results support the theory that cepharanthine inhibits the release of histamine from histamine-secreting cells in the gastric mucosa. It is suggested that histamine plays an important role in the neuro-humoral excitatory mechanism of gastric movement.