ANTRUM CAN CONTROL GASTRIC-EMPTYING OF LIQUID MEALS

Electrodes and force strain gauge transducers were implanted in dogs on the anterior gastroduodenal serosa for monitoring of contractile Percentage Activity and Gastric Work patterns and burst peak-to-peak durations, while fasting and after instillation of either isotonic sodium citrate or hypertonic 10% dextrose meals. The dogs were further divided at time of implantation into three surgical models: (i) otherwise intact stomachs or controls (CON), (ii) proximal gastric vagotomy with innervated antrum (PGV), and (iii) truncal vagotomy with posterior pylorectomy (TVP). Gastric emptying of the isotonic meal did not alter the normal interdigestive motility of the gastric antrum in any model. Whether instilled in the midst of or after a normal burst cycle, the hypertonic meal promptly inhibited antral contractions and significantly prolonged the burst peak-to-peak interval in animals with a vagally innervated antrum (CON, PGV). The inhibition lasted until >80% of the meal had emptied, followed by gradual return to normal burst activity. The inhibition ceased promptly when the half-emptied residual meal was aspirated from the stomach. The meal emptied faster, and inhibition was much less apparent in the TVP model. The data document that the vagally innervated gastric antrum (CON, PGV) controls emptying of hypertonic liquids by active inhibition of contractions. Antral denervation (TVP) produces contraction discoordination and impaired inhibition. © 1979.