The effects of vagal nerve stimulation on endoluminal release of serotonin and substance P into the feline small intestine

Scand J Gastroenterol. 1985 Mar;20(2):163-9. doi: 10.3109/00365528509089650.


Endoluminal release of serotonin (5-HT), substance P (SP), and motilin was quantitated after thoracic vagal nerve stimulation in the cat. In duodenum and jejunum, simultaneous release of these compounds was observed. In contrast, vagal stimulation did not augment the rate of luminal secretion of either 5-HT or SP in the distal ileum. Immunohistochemical studies demonstrated 5-HT in both enterochromaffin (EC) cells and nerves throughout the small bowel. However, we were unable to visualize any SP-containing EC cells in the cat, which suggests that the source of luminal SP in this species must be intramural nerves.

MeSH terms

  • Animals
  • Cats
  • Enterochromaffin Cells / metabolism
  • Fluorescent Antibody Technique
  • Ileum / physiology
  • Intestine, Small / physiology*
  • Jejunum / physiology
  • Male
  • Motilin / metabolism
  • Nerve Endings / metabolism
  • Perfusion
  • Serotonin / metabolism*
  • Substance P / metabolism*
  • Vagus Nerve / physiology*


  • Serotonin
  • Substance P
  • Motilin