AJP - Gastrointestinal and Liver Physiology, Vol 253, Issue 3 420-G424, Copyright © 1987 by American Physiological Society

ARTICLES

Vasoactive intestinal peptide stimulates protein phosphorylation in a colonic epithelial cell line

J. A. Cohn

The T84 colonic epithelial cell line was used to examine protein phosphorylation during neurohumoral stimulation of ion transport. T84 cell monolayers grown on collagen-coated filters were mounted in Ussing chambers to measure ion transport stimulated by vasoactive intestinal peptide. Maximal stimulation of active secretion occurred after 8-10 min of stimulation. Protein phosphorylation events accompanying stimulated secretion were detected using two-dimensional gel electrophoresis to resolve phosphoproteins from monolayers previously labeled using 32Pi. Within 8 min of exposure to vasoactive intestinal peptide, several phosphorylation events were detected, including a two- to fivefold increase in 32P incorporation into four soluble proteins with apparent molecular weights of 17,000, 18,000, 23,000, and 37,000. The same phosphorylation response occurs in monolayers stimulated by dibutyryl adenosine 3',5'-cyclic monophosphate (cAMP), suggesting that cAMP mediates these intracellular events. This study indicates that changes in protein phosphorylation accompany the secretory action of vasoactive intestinal peptide and suggests that T84 cells offer a useful model for studying the possibility that such phosphorylation events regulate enterocyte ion transport.

This article has been cited by other articles:

				C. S. Chew, J. A. Parente Jr., C.-J. Zhou, E. Baranco, and X. Chen Lasp-1 is a regulated phosphoprotein within the cAMP signaling pathway in the gastric parietal cell Am J Physiol Cell Physiol, July 1, 1998; 275(1): C56 - C67. [Abstract] [Full Text] [PDF]