Involvement of the Gut Chemosensory System in the Regulation of Colonic Anion Secretion

Figure 2

Schematic diagram of secretion stimulated by a bitter tastant (6-PTU) in colonic epithelial cells. Activation of apical T2R by luminal bitter tastant results in the synthesis of prostaglandin. This prostaglandin then induces an increase in intracellular cAMP concentration . Elevated activates the CFTR channels to mediate secretion. Activation of T2R simultaneously causes an increase in . The elevated modulates the -activated basolateral channels, providing a driving force for the exit of .