Polar Effects on Ion Transport and Cell Proliferation Induced by GC-C Ligands in Intestinal Epithelial Cells.

摘要: Guanylin receptor guanylate cyclase (GC-C) peaks in neonatal intestine and is involved either enterocyte proliferation or chloride secretion. The latter more potent when GC-C activator guanylin, its analog Escherichia coli heat-stable enterotoxin (ST), added to the mucosal rather than serosal side of intestinal monolayers. By using Ussing chambers, we investigated transepithelial ion transport their mechanisms response addition guanylin ST Caco-2 monolayers ileal specimens from neonates. activation showed a polar pattern effects. resulted cGMP-chloride secretion marginal proliferation. Conversely, induced proliferation, through MAP kinase ERK 1/2. Finally, inhibition ERK1/2 enhanced Isc increase but not stimulation, indicating that also acts as brake These data suggest guanylin/GC-C system plays key role early postnatal adaptation exploiting structure enterocyte.