E-Conference: Defining Calcium Entry Signals
How many stores are there?
8 June 2004
Certainly, the mechanism proposed by Reinhold could operate in the way described – and this may be the real situation in some cells, but it clearly is not the case in all cells.
We have demonstrated, for example both in HEK293 cells and in mouse parotid cells, that low concentrations of agonists (those that typically produce oscillatory Ca2+ signals) activate a conductance (the ARC channels) that displays fundamental biophysical characteristics that are entirely distinct from the conductance activated by high agonist concentrations (where sustained elevated Ca2+ signals are produced).
Of course, as yet, we can only say this for the cell types we have studied in such detail, and maybe the RBL cells operate differently. But, as we have published, the ARC channels are certainly present in RBL cells.
Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882