Enterotoxins and the enteric nervous system--a fatal attraction

Although there has been extensive investigation of the biochemical consequences of the interactions between bacterial enterotoxins and intestinal epithelial cells and the mechanisms by which they induce intestinal secretion, relatively little attention has been given to other aspects of the host response to these enterotoxins. There is now compelling evidence that the enteric nervous system has a major role in enhancing the secretory state induced by cholera toxin, the E. coli enterotoxins and possibly C. difficile toxin A. Cholera toxin for example is thought to activate a neural reflex via the release of 5-hydroxytryptamine from enterochromaffin cells. Neurotransmitters involved in the reflex include substance P and vasoactive intestinal polypeptide. Delineation of these neural pathways may offer new possibilities for the pharmacological control of enterotoxin-mediated secretion.