Table 2.
Effects of MK-886 (10 μM), AA861 (10 μM), MK571 (1 μM) and BAY-u9773 (0.1 μM) or vehicle on noradrenaline-induced contraction in aorta from all rat groups
| Methocel | L-NAME | L-NAME MK-886 | MK-886 | ||
|---|---|---|---|---|---|
| With endothelium | |||||
| Vehicle | pD2 | 6.9±0.2 (19) | 7.3±0.1* (22) | 6.9±0.1 (17) | 6.9±0.1 (8) |
| Emax (%) | 90.0±9.2 (19) | 74.7±7.7 (22) | 31.1±4.6 (17) | 95.8±4.5 (8) | |
| Emax (mg) | 2834±260 | 2281±186 | 1348±205 | 3370±312 | |
| MK-886 | pD2 | 6.7±0.2 (6) | 7.0±0.1** (8) | 6.8±0.1 (10) | 7.1±0.1 (6) |
| Emax | 79.0±4.2 (6) | 18.8±3.6** (8) | 24.7±4.0 (10) | 87.8±9.7 (6) | |
| AA861 | pD2 | 7.2±0.1 (5) | 7.2±0.1 (10) | 7.2±0.1 (10) | 6.9±0.1 (6) |
| Emax | 94.7±10.2 (5) | 47.0±8.4** (10) | 29.8±6.4 (6) | 102.9±16.9(6) | |
| MK571 | pD2 | 7.1±0.3 (6) | 7.0±0.1** (7) | 7.0±0.1 (7) | 6.9±0.1 (6) |
| Emax | 73.0±11.1 (6) | 43.4±9.4** (7) | 48.8±3.4 (7) | 93.3±7.8 (6) | |
| BAY-u9773 | pD2 | ND | 7.0±0.1* (9) | ND | ND |
| Emax | ND | 27.6±3.2** (9) | ND | ND | |
| Without endothelium | |||||
| Vehicle | pD2 | 7.4±0.1 (18) | 7.7±0.1 (17) | 7.7±0.1 (15) | 7.3±0.1 (8) |
| Emax (%) | 155.7±9.1 (18) | 122.6±5.6 (17) | 113.0±5.1 (15) | 150.6±4.1 (8) | |
| Emax (mg) | 3032±222 | 2322±207 | 2765±0.365 | 3195±234 | |
| MK-886 | pD2 | 7.5±0.1 (6) | 7.6±0.1 (7) | 7.6±0.2 (9) | 7.3±0.1 (6) |
| Emax | 134.2±8.0 (6) | 119.4±7.6 (13) | 95.9±7.2 (9) | 134.0±6.6 (6) | |
| MK571 | pD2 | 7.5±0.1 (4) | 7.8±0.1 (6) | 7.6±0.2 (6) | 7.3±0.1 (6) |
| Emax | 127.2±5.4 (4) | 132.1±7.0 (6) | 117.4±5.7 (6) | 146.7±9.8 (6) | |
| BAY-u9773 | pD2 | ND | 7.6±0.1 (6) | ND | ND |
| Emax | ND | 140.7±20.8 (6) | ND | ND | |
The Emax values of noradrenaline in the presence of vehicle are expressed as a percentage of the contraction elicited by 90 mM KCl and as mg of isometric force. All results are expressed as mean±s.e.m. of n aortic rings as indicated in parentheses.
*
P<0.05 vs Methocel, L-NAME-MK-886 and MK-886 rats; P<0.001 vs Methocel, MK-886 and L-NAME rats;
**
P<0.05 vs respective vehicle; ND: not determined.