Intracellular Calcium Mobilization in Response to Ion Channel Regulators via a Calcium-Induced Calcium Release Mechanism

The study investigated the effects of six ion channel modulators (amiodarone, dofetilide, furosemide, minoxidil, loxapine, and Nicorandil) on intracellular calcium release in prostate and breast cancer cell lines (PC3 and MCF7). Using ratiometric calcium imaging and patch-clamp experiments, it was found that these modulators increased intracellular calcium levels in a concentration-dependent manner, similar to clinical usage levels. The increase in calcium was significantly reduced when external calcium was chelated, suggesting that these modulators mobilize intracellular calcium through a calcium-induced calcium release mechanism. This mechanism may be crucial for understanding the action of these compounds.