Table 2.
Electrical responses to single stimulus pulse and ATP and NA in tibial artery smooth muscle from control, cold control and hibernated hamsters at 34 and 10°C
| Control | Cold control | Hibernated | |
|---|---|---|---|
| 34°C | |||
| Resting membrane potential (mV) | −64.5 ± 0.5 (15) | −63.9 ± 1.4 (11) | −62.5 ± 5.8 (7) |
| EJP | |||
| amplitude (mV) | 6.4 ± 0.2 (11) | 6.5 ± 0.3 (8) | 9.6 ± 0.5(6)*† |
| latency (ms) | 21.1 ± 0.8 (11) | 22.1 ± 1.4 (8) | 21.8 ± 1.2 (6) |
| time to peak amplitude (ms) | 43.9 ± 1.8 (11) | 44.5 ± 2.4 (8) | 44.9 ± 2.5(6) |
| total duration (ms) | 684.1 ± 34.0 (11) | 675.5 ± 36.2 (8) | 691.5 ± 35.0 (6) |
| Vm after ATP (100 μM) (mV) | 13.5 ± 1.4 (6) | 13.4 ± 1.3 (4) | 13.5 ± 1.2 (5) |
| Vm after NA (100 μM) (mV) | 6.1 ± 0.2 (5) | 5.9 ± 0.3 (4) | 6.0 ± 0.3 (4) |
| 10°C | |||
| Resting membrane potential (mV) | −59.0 ± 2.2 (8) | −59.0 ± 2.2 (7) | −55.5 ± 8.3 (7) |
| EJP | |||
| amplitude (mV) | 1.2 ± 0.4 (7)‡ | 1.3 ± 0.5 (6)‡ | 6.6 ± 0.8 (6)*†‡ |
| latency (ms) | 229.7 ± 5.3 (7)‡ | 224.7 ± 6.3 (6)‡ | 230.7 ± 6.3 (6)‡ |
| time to peak amplitude (ms) | 738.6 ± 31.2 (7)‡ | 734.4 ± 29.5 (6)‡ | 726.4 ± 30.2 (6)‡ |
| total duration (ms) | 2907.7 ± 42.9 (7)‡ | 3007.7 ± 37.9 (6)‡ | 3433.1 ± 42.0 (6)*‡ |
| Vm after ATP (100 μM) (mV) | 13.1 ± 1.6 (6) | 13.1 ± 1.3 (4) | 13.3 ± 1.5 (6) |
| Vm after NA (100 μM) (mV) | 0.3 ± 0.2 (5)‡ | 0.2 ± 0.3 (4)‡ | 0.2 ± 0.1 (4)‡ |
Data are means ± S.E.M. (number of observations).
*
P < 0.05vs. control
†
P < 0.05vs. cold control
‡
P < 0.05vs. 34°C of respective groups. Stimulation paramer: supramaximal voltage, 0.5ms, single pulse.