Neural and humoral factors influence gastric receptive relaxation in dogs.

To clarify the neural and humoral factors which control gastric receptive relaxation, the effects of various types of vagotomy or splanchnicotomy on receptive relaxation of the canine innervated corpus pouch were investigated. The influence of gastrin, histamine H1-receptor antagonist, and anti-histamine releasing agents on receptive relaxation were also examined. Selective proximal vagotomy or splanchnicotomy resulted in a slight disturbance in receptive relaxation. Truncal vagotomy produced a marked disturbance in receptive relaxation. Administration of tetragastrin potently inhibited receptive relaxation, however, recovery occurred by injecting a histamine H1-receptor antagonist. Increased serum gastrin induced by perfusion of the antrum with liver extract solution disturbed receptive relaxation and this response was inhibited by pretreatment with transamine, an inhibitor of histamine release from histamine secreting cells. These results indicate that receptive relaxation in the canine stomach is controlled not only by vagal and splanchnic nerves, but also by gastrin and histamine.