Abstract
Monensin is used as a sodium ionophore to examine the effect of Na + on cellular function in a variety of cell types. In the present study, we investigated the effects of different concentrations of monensin on the signal transduction system in exocrine parotid acinar cells. Monensin increased cytosolic free Na + concentration, measured by the Na + indicator sodium-binding benzofuran isophthalate in a concentration-dependent manner (0.01 to 100 μM). Likewise, monensin concentration-dependently increased amylase release and intracellular Ca 2+ concentration in the presence and the absence of extracellular Ca 2+. Low concentrations (0.01 to 1 μM) of monensin did not release Ca 2+ from non-mitochondrial intracellular pools in permeabilized cells with saponin but high concentrations (10 and 100 μM) of monensin which are of practical usage did. Monensin itself did not change the cyclic AMP accumulation, whereas high concentrations (10 and 100 μM) but not low concentrations (0.01 to 1 μM) of monensin inhibited cyclic AMP accumulation elevated by isoproterenol in the presence and absence of extracellular Na +. These results indicate that high concentrations of monensin, which are practically used, have nonspecific actions in rat parotid acinar cells, and lower concentrations of monensin are recommended for use as a sodium ionophore.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
