Pretreatment Condition | Calcium Concentration | |
---|---|---|
Baseline | Peak to 50 mM KCl | |
nM | ||
No [Ca2+]i | 104 | 138 |
BAPTA/No [Ca2+]i | 103 | 147 |
+[Ca2+]i | 153 | 417 |
BAPTA/+[Ca2+]i | 136 | 252 |
PC12 cells were pretreated with 50 μM BAPTA-AM or vehicle for 15 min followed by incubation with 2 μM fura-2 for 20 min in KRB prepared with (+) or without (No) 1.2 mM CaCl2. Peak values were obtained when cells were challenged with 50 mM KCl. The intracellular free calcium concentration ([Ca2+]i) was measured using dual-wavelength spectrofluorometer as described underMaterials and Methods. The results are the averages of two experiments that did not differ by more than 5%.