Table II. Properties of RyR1 channels from normal and HF skeletal muscle.
| Channels active at resting [Ca2+] | Channels with substates | Channels exhibiting coupled gatinga | Open time | Closed time | |
|---|---|---|---|---|---|
| ms | ms | ||||
| Normal skeletal muscle | 0/53 (0%) | 1/53 (2%) | 6/53 (11%) | 6.8 ± 1.3 | 9.7 ± 1.2 |
| HF skeletal muscle | 16/42 (38%)b | 33/42 (78%)c | 0/42 (0%)c | 1.4 ± 0.3c | 1.2 ± 0.2c |
a
We previously showed that in normal skeletal muscle, ∼10% of RyR1 channels remain physically coupled to one another during isolation and insertion into the bilayer, so the level of coupled gating observed in the present study for RyR1 from control skeletal muscle is comparable to that in normal non-HF RyR1 (Marx et al., 1998).
b
P < 0.01 for HF versus normal skeletal muscle.
c
P < 0.001 for HF versus normal skeletal muscle.