Abstract
The human colonic epithelial goblet cell line HT29-Cl.16E was used to test whether stimulated Cl- transport is involved in the mucin exocytotic response to an increase in intracellular cyclic AMP by measuring in parallel the short-circuit current (Isc) and mucin exocytosis. Addition of 50 microM forskolin to HT29-Cl.16E cells resulted in a 2-fold stimulation of mucin release and an increase in Isc by 20 microA/cm2. To evaluate the requirement for cosecretion of Cl-, the Cl- flux was altered by three different manipulations: (1) Cl- in the medium was replaced by the poorly transported anion gluconate; (2) basolateral Cl- influx through the Na(+)-K(+)-2Cl- cotransporter was inhibited by bumetanide; and (3) an inward Cl- flux through the apical plasma membrane was generated by reversing the Cl- gradient. These manipulations did not change the forskolin-stimulated mucin release and thereby provide evidence that Cl- movements are not required for fusion of mucin granules with the plasma membrane.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.