Table 4.
Effect of electrical stimulation on the relative uptake of [14C]sucrose and 36Cl in rat EDL muscle in vitro
| Experimental conditions | [14C]sucrose space | 36Cl space |
| % | % | |
| Rest | 24.7 ± 1.8 (6) | 23.6 ± 0.4 (6) |
| 60-Hz stimulation, 120 s | 19.4 ± 0.4 (6) | 22.6 ± 0.6 (6) |
Isolated rat EDL muscles were mounted in force transducers for isometric contractions and preequilibrated for 15 min in KR buffer at 30°C, followed by 90 min of incubation in KR buffer with 0.4 µCi/ml 36Cl or 0.2 µCi/ml [14C]sucrose and 1 mM of unlabelled sucrose (as a carrier). Finally, six of the muscles were stimulated for 120 s at 60 Hz using 0.2-ms, 10-V pulses. Six other muscles were resting. The muscles were blotted on dry filter paper, weighed, and taken for counting of 36Cl and 14C activity. On the basis of the 36Cl and 14C activity of the incubation medium, the relative uptake of the isotopes was expressed as a percentage and given as mean ± SEM, with the number of muscles in parentheses. For example, a 36Cl uptake of 23.6% means that 1 g of muscle (wet weight) has taken up 36Cl corresponding to that contained in 0.236 ml of incubation medium.