Real-time detection of serotonin release from enterochromaffin cells of the guinea-pig ileum

Neurogastroenterol Motil. 2004 Oct;16(5):511-4. doi: 10.1111/j.1365-2982.2004.00572.x.

Abstract

Serotonin (5-hydroxytryptamine; 5-HT) containing enterochromaffin (EC) cells may detect chemical or mechanical stimuli in the intestinal lumen and respond with release of 5-HT. The aim of this study was to use real-time electrochemical detection methods to detect release of 5-HT from small numbers of EC cells. In guinea-pig ileum, basal release of 5-HT from the unstimulated, unparalyzed intestine was composed of individual release events (8.4 +/- 1.8 events, 0.33 +/- 0.06 Hz) of different amplitudes but with similar kinetics. Local compression of the mucosa with the electrode evoked peak 5-HT release of 12.3 +/- 2.8 micromol L(-1) with a sustained release of 3.0 +/- 0.7 micromol L(-1). Brief application of acetylcholine (ACh) or carbachol elicited a transient peak (5.7 +/- 1.3 micromol L(-1) occurring at 35 +/- 18 s, n = 9) followed by cyclic release of 5-HT (9.7 +/- 2.2 events, 0.40 +/- 0.13 Hz, n = 6). This study shows that the release of 5-HT occurs rapidly as individual events from a small number of cells and can reach very high concentrations locally.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carbon
  • Electrochemistry
  • Electrodes
  • Enterochromaffin Cells / metabolism*
  • Guinea Pigs
  • Ileum / metabolism*
  • Intestinal Mucosa / metabolism*
  • Organ Culture Techniques
  • Patch-Clamp Techniques / methods*
  • Serotonin / analysis*
  • Serotonin / metabolism

Substances

  • Serotonin
  • Carbon