Table 1.

Summary of experimental conditions, compound concentrations and cellular targets.

Compound	Abbr.	Conc.	Cellular target	Comment
culture medium	medium	—	—	Physiological condition
PBS w/o Ca2+, Mg2+	PBS	—	—	Absence of extracellular Ca2+
PBS w/ Ca2+, Mg2+	PBSC	—	—	Control for PBS
2-Aminoethoxy-diphenyl borate	2-APB	75 µM	IP3-receptors in the ER membrane43	Also interferes with some TRP channels44
Ryanodine	Ry	50 µM	Ryanodine receptors in the ER membrane45	Also used in combination with 2-APB (50 µM Ry + 100 µM 2-APB)
CGP37157	CGP	20 µM	Mitochondrial Na+/Ca2+-exchanger46
Ruthenium Red	RR	100 µM	Heat-activated TRP channels47	Also blocks intracellular channels, but does not cross the cell membrane48
Lidocaine	Lid	100 µM	Voltage-dependent sodium channels49	Sodium currents during an action potential would activate voltage-dependent calcium channels50
Cyclosporine A	CspA	5 µM	mitochondrial membrane permeability transition pore35,36

Experiments were designed to inhibit specific pathways of cellular calcium signaling as well as study the overall impact of extracellular calcium.