Features of excitation–response coupling
| . | Coupling . | . | . | . | |||
|---|---|---|---|---|---|---|---|
. | E-S . | Cardiac E-C . | Skeletal E-C . | E-T . | |||
| Input–output speed | ms | ms | ms | s–min | |||
| Relationship to voltage (mV/e-fold change) | 4.3a | 6.2b | 3.1c | 5.6 | |||
| Requires Ca2+ flux through membrane Ca2+ channels | Yes | Yes | No | Yes | |||
| Voltage dependence above and beyond Ca2+ flux | No | No | Yes | Yes | |||
| Locally mediated signaling | Yes | Yes | Yes | Yes | |||
| Requires Ca2+ release from stores | No | Yes | Yes | No | |||
| Target of Ca2+ or conformational coupling | synaptotagmin | RyRs | RyRs | CaM/CaMKII | |||
| . | Coupling . | . | . | . | |||
|---|---|---|---|---|---|---|---|
. | E-S . | Cardiac E-C . | Skeletal E-C . | E-T . | |||
| Input–output speed | ms | ms | ms | s–min | |||
| Relationship to voltage (mV/e-fold change) | 4.3a | 6.2b | 3.1c | 5.6 | |||
| Requires Ca2+ flux through membrane Ca2+ channels | Yes | Yes | No | Yes | |||
| Voltage dependence above and beyond Ca2+ flux | No | No | Yes | Yes | |||
| Locally mediated signaling | Yes | Yes | Yes | Yes | |||
| Requires Ca2+ release from stores | No | Yes | Yes | No | |||
| Target of Ca2+ or conformational coupling | synaptotagmin | RyRs | RyRs | CaM/CaMKII | |||