Table 12.
Adenylyl cyclase activity and ADP ribosylation in the absence and presence of cholera toxin (20 μg/mL) as well as Gs-protein content in right ventricle from the control as well as at early (4 weeks), moderate (8 weeks) and severe (16 weeks) stages of heart failure due to myocardial infarction (MI) in rats.
| Parameters | Control | Early Failure Stage (4 Weeks MI) |
Moderate Failure Stage (8 Weeks MI) |
Severe Failure Stage (16 Weeks MI) |
|---|---|---|---|---|
|
A. Adenylyl cyclase activity (pmol/cyclic AMP/10 min/mg protein): |
||||
| Basal | 148 ± 7.6 | 115 ± 5.8 * | 208 ± 17.9 * | 200 ± 14.5 * |
| Cholera Toxin | 292 ± 15.8 | 240 ± 8.9 * | 486 ± 23.7 * | 478 ± 26.2 * |
| B. ADP ribosylation | ||||
| Cholera toxin catalyzed at | ||||
| 45 KD (% control) | 100 | 98 ± 8 | 148 ± 12 * | 137 ± 12 * |
| 52 KD (% control) | 100 | 97 ± 10 | 144 ± 10 * | 129 ± 12 |
| C. G-protein content | ||||
| Gs protein 45 KD (% of control) |
100 | 105 ± 10 | 300 ± 14 * | 213 ± 22 * |
| Gs protein 52 KD (% of control) |
100 | 101 ± 9 | 208 ± 10 * | 152 ± 10 * |
Values are mean ± SE of five experiments. ADP ribosylation and Gs-protein contents were measured at 45 KD and 52 KD bands. The data are based on information in our paper, Sethi et al., 1998 [31]. * p < 0.05 vs. respective control.