The mechanism by which inositol 3,4,5,6-tetrakisphosphate (Ins(3,4,5, 6)P4) regulates chloride (Cl-) secretion was evaluated in the colonic epithelial cell line T84 using whole cell voltage clamp techniques. Our studies focused on the calcium-dependent chloride conductance (gClCa) that was activated either by mobilizing intracellular calcium (Cai) stores with thapsigargin or by introduction of ...

Devor, Daniel C., and Raymond A. Frizzell. Modulation of K1 channels by arachidonic acid in T84 cells. II. Activation of a Ca21-independent K1 channel. Am. J. Physiol. 274 (Cell Physiol. 43): C149–C160, 1998.—We used singlechannel recording techniques to identify and characterize a large-conductance, Ca21-independent K1 channel in the colonic secretory cell line T84. In symmetric potassium gluc...

BACKGROUND The antimicrobial activity of silver nanoparticles (AgNP) has led to interest in their use in consumer products such as food contact materials, utensils, and storage containers. Incorporation of these materials into items intended for food processing and storage suggests that consumer use of these products could result in gastrointestinal exposure to AgNP, should the nanoparticles mi...

Treatment of HT-29 cells with phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C (PKC), induces MUC2 expression. To investigate the role of PKC in regulating mucin genes in intestinal cells, we examined the regulation of MUC1, MUC2, MUC5AC, MUC5B, and MUC6 expression in two human mucin-producing colonic cell lines, T84 and HT29/A1. T84 and HT29/A1 cells (at 80-90% confluenc...

The induction of interleukin-8 (IL-8) in vitro has been suggested to correlate with the reactogenicity of Vibrio cholerae vaccine candidates. V. cholerae vaccine candidate 638, a hemagglutinin protease/hap-defective strain, was recently reported to be well tolerated in human volunteers, suggesting a role for Hap in reactogenicity. We examined the role of hap in the induction of IL-8 in intestin...

BACKGROUND Cholera toxin (CT) acts on intestinal epithelial cells both directly and indirectly via activation of a secretory neural reflex. The reflex may release acetylcholine as one of its final neurotransmitters. This opens up the possibility of a third mechanism of action for CT, namely a synergistic interaction between two secretagogues acting on different second messenger systems within t...

OBJECTIVE Bile acids are important regulators of intestinal physiology, and the nuclear bile acid receptor, farnesoid X receptor (FXR), is emerging as a promising therapeutic target for several intestinal disorders. Here, we investigated a role for FXR in regulating intestinal fluid and electrolyte transport and the potential for FXR agonists in treating diarrhoeal diseases. DESIGN Electrogen...