| IP3R |
| RyR |
| Skel muscle |
| + |
| +++ |
| Smooth m. |
| +++ |
| + |
| Neurons |
| +++ |
| +++ |
| IP3 |
| Activates |
| None |
| Ryanodine |
| None |
|
|
| Locks |
|
| open/closes |
|
| Caffeine (5 mM) |
| Inhibits |
| Activates |
| Ca2+ |
|
|
|
| IP3R1 - |
||
| biphasic |
||
| IP3R2/3 -
opens |
||
| biphasic |
| RR |
| None |
| inhibits |
| Heparin |
| inhibits |
| activates |