Capsaicin-sensitive vagal afferent fibers and stimulation of gastric acid secretion in anesthetized rats

Helen E Raybould, Yvette Taché

Research output: Contribution to journalArticlepeer-review

64 Scopus citations


The sensory neurotoxin, capsaicin, has been used to study the reflex pathway by which gastric acid secretion increases in response to gastric distension in urethane-anesthetized rats. Capsaicin (1%) or vehicle (10% Tween 80 in olive oil) was applied directly to each cervical vagus 7-14 days prior to experiments. Gastric acid secretion was measured in acute gastric fistula rats by continuous intragastric perfusion and back titration or by flushing the gastric contents with saline every 10 min. Gastric acid secretion was stimulated by distension (5 ml for 6 min) or by injection of secretagogues (histamine 5.0 mg/kg s.c., bethanchol 0.5 mg/kg s.c. or pentagastrin 16 μg/kg per h i.v.). Gastric distension increased gastric acid secretion 6.2 times over basal gastric acid secretion in vehicle-treated control rats; capsaicin pretreatment significantly reduced this response by 40%. Bilateral cervical vagotomy significantly reduced the secretory response to gastric distension in the vehicle-treated group to a level not significantly different from capsaicin-treated rats. The secretory response to histamine was reduced by 42% in capsaicin-treated rats compared to vehicle pretreatment whereas the responses to pentagastrin and bethanechol were unaltered. These results indicate that capsaicin-sensitive vagal afferent fibers eediate the vagal portion of the secretory response to gastric distention; in addition these afferents play a role in the gastric acid secretory response to histamine.

Original languageEnglish (US)
Pages (from-to)237-243
Number of pages7
JournalEuropean Journal of Pharmacology
Issue number2
StatePublished - Aug 22 1989


  • (Cholinergic stimulation)
  • Capsaicin
  • Gastric acid secretion
  • Gastric distension
  • Histamine
  • Pentagastrin
  • Vagus nerve

ASJC Scopus subject areas

  • Cellular and Molecular Neuroscience
  • Pharmacology


Dive into the research topics of 'Capsaicin-sensitive vagal afferent fibers and stimulation of gastric acid secretion in anesthetized rats'. Together they form a unique fingerprint.

Cite this