__________ is secreted by the ileum and colon and stimulates intestinal secretion of Cl^- thereby causing elimination of NaCl and water in the feces. A)Guanylin B)Motilin C)Serotonin D)Nitric oxide

Question

Quizplus · Accepted Answer

Guanylin is a peptide hormone secreted by the ileum and colon. It acts on the intestinal epithelium to stimulate the secretion of chloride ions (Cl-) and bicarbonate ions (HCO3-) into the lumen of the gut. This causes water to flow into the gut, resulting in increased fecal volume and diarrhea. Guanylin exerts its effect by binding to guanylate cyclase (GC-C) receptors on the luminal surface of intestinal epithelial cells, leading to a cGMP-mediated increase in Cl- and HCO3- secretion.

__________ Is Secreted by the Ileum and Colon and Stimulates