Relation between electrical and mechanical activity in esophageal smooth muscle

Publisher Website
Google Scholar
Abstract
Experiments were performed in anesthetized opossums. Electrical and mechanical activity was recorded simultaneously from the esophageal body at 5, 3 and 1 cm above the lower esophageal sphincter (LES). Esophageal responses were evoked by electrical stimulation of vagal efferents or by induced swallowing. Electrical and mechanical activity was associated in 86% and dissociated in 14% of the 1200 responses examined. The frequency of dissociation was dependent on the site in the esophagus and the frequency of vagal efferent stimulation (P < 0.05). The interval between the onset of electrical and mechanical events, called electromechanical delay had a regional gradient: 5 cm above LES > 3 cm > 1 cm (P < 0.01). This delay was also dependent on the frequency of stimulation. The amplitude of spike burst and the number of spikes in a burst closely correlated with the amplitude of contraction. Electromechanical responses and dissociations are evidently dependent on the regional level in the esophagus and the frequency of vagal stimulation.

This publication has 0 references indexed in Scilit: