Table 1.
Quantification of frequency and amplitude of contraction
| 0 h |
2 h |
4 h |
6 h |
8 h |
10 h |
|||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Specimen | F, % | A, % | F, % | A, % | F, % | A, % | F, % | A, % | F, % | A, % | F, % | A, % |
| Control | 100 | 100 | 71 ± 9.6† | 255 ± 28† | 65 ± 3.2† | 239 ± 20† | 104 ± 6.1 | 133 ± 16 | 170 ± 23† | 17 ± 0.9† | 159 ± 19† | 22 ± 0.72† |
| Bim-1 | 100 | 100 | 86 ± 8.4 | 266 ± 22* | 96 ± 5.8 | 189 ± 19* | 100 ± 5.8 | 152 ± 21 | 106 ± 11* | 131 ± 17* | 111 ± 10 | 114 ± 14 |
| Bim-1 + TTX | 100 | 100 | 87 ± 8.1 | 248 ± 27 | 109 ± 8.8* | 190 ± 24* | 110 ± 11 | 175 ± 9.3* | 109 ± 14* | 123 ± 18* | 115 ± 13* | 119 ± 15* |
Values represent means ± SE. Summary of the data for the frequency (F) and amplitude (A), as a percentage of the initial F and A at time 0 (100%), of spontaneous contractions recorded over 10 h for control, and of muscle strips in the presence of bisindolylmaleimide 1 (Bim-1) alone and Bim-1 plus tetrodotoxin (TTX). Note the significant decline in A and increase in F of the control at 8 h compared with Bim-1 and Bim-1 plus TTX. Bim-1 and Bim-1 plus TTX maintained a high A of spontaneous contractions throughout the period of the recording, 131 and 123%, respectively, at 8 h, compared with control of only 17% of that recorded at time 0. Whereas the F increased significantly in control to 170% at 8 h compared with time 0, there was no significant change for Bim-1 and Bim-1 plus TTX (106 and 109%, respectively) compared to time 0. The A of spontaneous contractions for control at 8 h (17%) was also significantly different from Bim-1 (131%) and Bim-1 plus TTX (123%) at 8 h. This was also true for F at 8 h where the control was 170% and Bim-1 and Bim-1 plus TTX were 106 and 109%, respectively. There was no significant change in the F at 8 h for Bim-1 and Bim-1 plus TTX compared to time 0; however, changes in A were just barely significant. Data also indicate that TTX did not affect the ability of Bim-1 to maintain a high level of spontaneous contraction. Data represent the summary of 6 separate experiments (n = 6).
P < 0.05, significantly different from control;
P < 0.05, significantly different from initial measurement at time 0.