Luminal capsaicin inhibits fluid secretion induced by enterotoxin E. coli STa, but not by carbachol, in vivo in rat small and large intestine

Exp Physiol. 1996 Mar;81(2):313-5. doi: 10.1113/expphysiol.1996.sp003935.


The enterotoxin E. coli STa induced fluid secretion in the rat jejunum, ileum and proximal colon in vivo that was greatly inhibited by the co-presence of luminal capsaicin, which is a specific neural toxin of afferent C fibres. The same dose of capsaicin had no effect on the fluid secretion activated by carbachol in the jejunum, ileum and proximal colon. Afferent C fibres appear to be involved in the activation by STa of fluid secretion in the rat intestine in vivo.

MeSH terms

  • Afferent Pathways / physiology
  • Animals
  • Capsaicin / pharmacology*
  • Carbachol / pharmacology*
  • Chlorides / metabolism
  • Enterotoxins / antagonists & inhibitors
  • Enterotoxins / pharmacology
  • Escherichia coli
  • Intestinal Secretions / drug effects*
  • Intestinal Secretions / physiology
  • Nerve Fibers / drug effects
  • Nerve Fibers / metabolism
  • Neurotoxins / pharmacology
  • Rats
  • Rats, Inbred Strains


  • Chlorides
  • Enterotoxins
  • Neurotoxins
  • Carbachol
  • Capsaicin