[Effects of propantheline on the motor activity of the normal human esophagus]

The aim of this study was to examine the action of orally administrated propantheline bromide, an anticholinergic agent, on esophageal motor function. To evaluate these effects a double blind randomized study was carried out in ten normal volunteers. An optimal effective dose for each subject was determined according to the Sun and Shay method. Esophageal motor activity following dry and wet swallow was markedly altered by propantheline. This drug: a) dramatically lowered the peristaltic wave amplitude in the smooth muscle part of the esophagus (P less than 0.001); b) decreased the wave velocity in the proximal part of the smooth muscle (P less than 0.05), and c) increased the frequency of both the non peristaltic and repetitive waves (P less than 0.001). On the other hand propantheline weakly but significantly diminished the lower esophageal sphincter resting pressure (P less than 0.05). These results suggest that: a) the peristaltic function of the human esophageal smooth muscle is greatly dependent on muscarinic neurotransmission, and b) in patients with gastroesophageal reflux, orally as well as parenterally administrated anticholinergic agents are contraindicated.