cAMP-independent chloride secretion activated by a vasoactive intestinal peptide in a monolayer culture of human bronchial epithelial cells.
To investigate the effects of vasoactive intestinal peptide (VIP) on Cl- transport across normal human bronchial epithelial (NHBE) cells grown in a monolayer, changes in short-circuit current (Isc) were measured in Ussing chamber systems. In the presence of 10(-4) M amiloride, the addition of VIP to the serosal solution led to an increase in the Isc in a concentration-dependent manner, the 50% effective concentration (EC50) being 2.6 x 10(-11) M. However, the addition of 10(-5) M forskolin had little effect on the increase in Isc. On the other hand, in the intracellular cAMP measurement, 10(-5) M forskolin remarkably increased the cAMP levels, but 10(-7) M VIP did not. This result suggests that Cl- secretion by VIP is not related to the raised intracellular cAMP levels in NHBE cells.
Tokunaga
T
T
Research Department, Sawai Pharmaceutical Co., Ltd., Osaka, Japan.
Kiso
T
T
Namikawa
T
T
Ohtsubo
Y
Y
D001980:Bronchi / Q000166:cytology / Q000378:metabolism*; D002478:Cells, Cultured; D002712:Chlorides / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004847:Epithelial Cells / Q000378:metabolism; D006801:Humans; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism*
D002712:Chlorides; D014660:Vasoactive Intestinal Peptide; D000242:Cyclic AMP