Correlation between electrophysiological phenomena and transport of macromolecules in intestinal epithelium

Summary

This review discuss some recent findings in the study of the regulation of the permeability of the intestinal epithelial layer. Comparison of electrical phenomena and transport of macromolecules suggests that secretory activity and increased transepithelial transport of macromolecules are related when secretion is mediated by the Ca²⁺ and PKC dependend pathways. The transport of the macromolecules is via the transcellular and via the paracellular route. The barrier function of the intestinal epithelium may be diminished during nervous (acetylcholine)‐ and immuno‐(histaminc) mediated secretion. It is hypothesised that some bacterial toxins may also induce Ca²⁺ and PKC dependent secretion and thereby can reduce the epithelial barrier. The cAMP and cGMP mediated secretion, which can be recognised by their long‐lasting transepithelial potential changes, are not coupled to increased transepithelial transport of macromolecules. Some forms of secretory diarrhea may therefore be related to the development of food‐allergy or inflammation.

Notes

Institute Neurobiology, University of Amsterdam, Kruislaan 320, 1098 SM Amsterdam, the Netherlands. E‐mail: [email protected].