Comparison of the [Ca2+] changes that occurred in some regions of the subplasma membrane space and bulk cytoplasm
| Subplasma membrane space | Peak [Ca2+]PM (ΔF/F0) | Rise time (ms) | Rise slope (ΔF/F0/s) | Decay time (ms) | Decay slope (ΔF/F0/s) | n |
| Average | 5.2 ± 0.7 | 320 ± 69 | 12.8 ± 2.2 | 3,730 ± 2,346 | −1.5 ± 0.4 | 6 |
| Regions | 7.3 ± 1.4 | 118 ± 18 | 41 ± 10.9 | 851 ± 149 | −5.9 ± 1.3 | 14 |
| Bulk cytoplasm | Peak [Ca2+]c (ΔF/F0) | Rise time (ms) | Rise slope (ΔF/F0/s) | Decay time (ms) | Decay slope (ΔF/F0/s) | n |
| Average | 6.8 ± 1.2 | 343 ± 46 | 17.8 ± 5.2 | 3,496 ± 1,141 | −2.0 ± 0.7 | 6 |
| Regions | 7.2 ± 0.6 | 345 ± 30 | 17.9 ± 3.2 | 2,992 ± 322 | −1.7 ± 0.2 | 14 |
| Subplasma membrane space | Peak [Ca2+]PM (ΔF/F0) | Rise time (ms) | Rise slope (ΔF/F0/s) | Decay time (ms) | Decay slope (ΔF/F0/s) | n |
| Average | 5.2 ± 0.7 | 320 ± 69 | 12.8 ± 2.2 | 3,730 ± 2,346 | −1.5 ± 0.4 | 6 |
| Regions | 7.3 ± 1.4 | 118 ± 18 | 41 ± 10.9 | 851 ± 149 | −5.9 ± 1.3 | 14 |
| Bulk cytoplasm | Peak [Ca2+]c (ΔF/F0) | Rise time (ms) | Rise slope (ΔF/F0/s) | Decay time (ms) | Decay slope (ΔF/F0/s) | n |
| Average | 6.8 ± 1.2 | 343 ± 46 | 17.8 ± 5.2 | 3,496 ± 1,141 | −2.0 ± 0.7 | 6 |
| Regions | 7.2 ± 0.6 | 345 ± 30 | 17.9 ± 3.2 | 2,992 ± 322 | −1.7 ± 0.2 | 14 |
The rise time, rise slope, decay time, and decay slope were measured from the changes that occurred between 20 and 80% of the peak ΔF/F0 values. The “average” value has been derived from the entire region that was visible in TIRF. That area was used to generate an “area of interest,” which was applied to obtain the average change that occurred in the bulk cytoplasm as measured in wide-field epifluorescence. “Regions” were 2 × 2–pixel areas. Rates of change in regions of the subplasma membrane space were substantially faster than those occurring in the same regions in the bulk cytoplasm. n values are from six different cells.