Erythromycin gastrokinetic activity is partially vagally mediated

Abstract

Erythromycin overcomes postvagotomy gastroparesia in patients without a distal stomach and functional pylorus. We investigate the role of the vagus in gastric emptying increased by erythromycin, using a model that preserves the physiology of the distal stomach and pylorus. The effects of erythromycin lactobionate (10 mg/kg) on transpyloric flow pattern and pyloric resistance were evaluated during repetitive bilateral vagal cooling in anesthetized pigs. Vagal cooling during erythromycin infusion produced a marked decreased of pyloric outflow (23 ± 1.1 vs. 50 ± 2.6 ml/min) related to a reduced stroke volume of the flow pulses (7.8 ± 3.31 vs. 14.1 ± 2.44 ml). The amplitude and frequency of gastric and duodenal pressure events were unchanged or slightly reduced during vagal cooling. The smaller stroke volume of flow pulse was the consequence of increased pyloric resistance (6.2 ± 1.98 vs. 2.3 ± 0.21 mmHg ⋅ ml−1 ⋅ s), which is associated with changes in the temporal relationship between a pyloric pressure event and flow pulse. In conclusion, erythromycin activity on the pylorus requires the integrity of vagal pathways. Enhancement of gastric outflow by erythromycin is also modulated by the vagus, since pyloric resistance was able to overcome increased gastric motility.

The relationship between gastric motility and nausea: Gastric prokinetic agents as treatments

“…The authors also found that in addition to facilitation of gastric cholinergic activity, low concentrations of motilin directly increased the activity of a population of gastric vagal afferent fibres. These data substantiate previous indirect evidence suggesting that motilin receptor agonists could influence vagal nerve activity (e.g., Mathis and Malbert (1998);Suzuki et al (1998)) and raise the possibility that erythromycin reduced emesis by stimulating gastric emptying and/or modulating an emetic pathway via changes in vagal afferent nerve activity. A further action of erythromycin within the brain remains a possibility but at present, there is no clear evidence for a direct ability of motilin to affect brain functions .…”

GI Complications in Patients Receiving Mechanical Ventilation

“…129 -131 While erythromycin acts via motilin receptors, an intact vagal pathway has been shown to be necessary for its GI effects. 132,133 Metoclopramide is another prokinetic agent that is useful in the treatment of gastroduodenal hypomotility. 134,135 The precise mechanism of action is unclear, but metoclopramide improves antroduodenal coordination and reverses the inhibitory effects of dopamine on GI motility.…”

Inferior vagal ganglion galaninergic response to gastric ulcers

“…Vagal nerves are considered to play an important role in the regulation of stomach functions [50][51][52][53][54]. In the porcine stomach, vagal afferents constitute up to 80% of afferent pyloric innervation, while only a minority of cell bodies are dispersed within the bilateral spinal ganglia of the thoracic and lumbar neuromeres [7].…”