Effects of propranolol (1 μM; n = 6), atenolol (1 μM; n = 5), ICI 118,551 (1 μM; n = 6), and butoxamine (3 μM; n = 6) on RbCC relaxations evoked by ACh (0.6 nmol), metaproterenol (MET; 100 nmol), isoproterenol (ISO; 100 nmol), ritodrine (RIT; 100 nmol), fenoterol (FEN; 100 nmol), and TA 2005 (TA; 100 nmol) RbCC relaxations induced by MET, ISO, RIT, FEN, and TA were expressed (mean ± S.E.) relative to the submaximal relaxation induced by glyceryl trinitrate, which was taken as 100%.
RbCC Relaxation (%) | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Propranolol | Atenolol | ICI 118,551 | Butoxamine | ||||||||||||
| Control | Treated | Control | Treated | Control | Treated | Control | Treated | ||||||||
| ACh | 88 ± 25 | 90 ± 28 | 112 ± 15 | 105 ± 18 | 72 ± 10 | 69 ± 8 | 91 ± 16 | 73 ± 12 | |||||||
| MET | 52 ± 11 | 48 ± 9 | 73 ± 7 | 76 ± 8 | 50 ± 8 | 56 ± 10 | 34 ± 4 | 32 ± 6 | |||||||
| RIT | 66 ± 10 | 61 ± 8 | 107 ± 10 | 112 ± 13 | 84 ± 11 | 93 ± 15 | 66 ± 6 | 71 ± 9 | |||||||
| TA | 85 ± 13 | 71 ± 10 | 87 ± 11 | 90 ± 14 | 91 ± 13 | 86 ± 9 | 108 ± 18 | 96 ± 13 | |||||||
| FEN | 70 ± 8 | 62 ± 7 | 93 ± 9 | 99 ± 12 | 75 ± 7 | 87 ± 10 | 57 ± 9 | 65 ± 10 | |||||||
| ISO | 45 ± 5 | 6 ± 3* | 70 ± 8 | 65 ± 11 | 61 ± 12 | 13 ± 4* | 36 ± 5 | 9 ± 4* | |||||||
↵* P < 0.01 compared with the respective control