Table 1.
CRAC Channel Properties in Resting and Activated Human T Lymphocytes and in Jurkat T Cells
| Property | Resting T cells | Activated T cells | Jurkat T cells |
|---|---|---|---|
| Activation by passive store depletion | Yes | Yes | Yes |
| IP3 accelerates activation | Yes | ND | Yes |
| Single channel Na+conductance | 41 pS | 41 pS | 38–40 pS |
| Open probability (−120 mV) | >0.95 | >0.95 | >0.94 |
| Ratio of Na+to Ca2+ current | ND | 81.4 ± 2.4 (2 mM Ca2+) | 27 (20 mM Ca2+) |
| External Ca2+ block (−90 mV) | K d = 4 μM | K d = 4 μM | K d = 5 μM |
| Mg2+-dependent inactivation | Yes | Yes | Yes |
| Permeability to NMDG+ | <0.01 | <0.01 | <0.01 |