Table 1.
The plasma concentration of norepinephrine and epinephrine.
| WKY |
SHR |
|||||
|---|---|---|---|---|---|---|
| N | Norepinephrine (nM) | Epinephrine (nM) | N | Norepinephrine (nM) | Epinephrine (nM) | |
| PROTOCOL 1: ROLE OF β1+2AR IN CATECHOLAMINE RELEASE | ||||||
| PBS + tyramine | 13 | 21.7 ± 0.9 | 3.8 ± 1.0 | 16 | 26.7 ± 1.3** | 5.7 ± 0.7 |
| Atenolol + tyramine (peripheral β1AR ant.) | 7 | 11.6 ± 0.8‡‡ | 2.6 ± 0.4 | 8 | 13.8 ± 1.1‡‡ | 7.9 ± 3.0 |
| CGP20712A + tyramine (β1AR ant.) | 7 | 11.4 ± 1.0‡‡ | 2.9 ± 0.8 | 7 | 16.7 ± 2.4‡‡ | 7.2 ± 3.5 |
| Metoprolol + tyramine (β1AR ant.) | 6 | 9.3 ± 0.7‡‡ | 1.8 ± 0.7 | 6 | 14.6 ± 1.2‡‡ | 13.4 ± 4.5 |
| ICI-118551 + tyramine (β2AR ant.) | 6 | 16.3 ± 1.9‡ | 3.2 ± 1.5 | 7 | 15.0 ± 1.4‡‡ | 5.4 ± 1.1 |
| Nadolol + tyramine (peripheral β1+2AR ant.) | 7 | 10.2 ± 2.5‡‡ | 1.8 ± 1.0 | 6 | 13.1 ± 1.9‡‡ | 7.4 ± 2.9 |
| PROTOCOL 2: ROLE OF THE ADRENALS IN β1/2AR MODULATION OF NOREPINEPHRINE RELEASE | ||||||
| AdrX + PBS + tyramine | 7 | 23.1 ± 2.5 | 0.6 ± 0.6§§ | 8 | 31.8 ± 3.1 | 0.2 ± 0.1§§ |
| AdrX + atenolol + tyramine | 6 | 9.8 ± 0.4‡‡ | 0.0 ± 0.0 | 8 | 23.0 ± 2.4‡ | 0.0 ± 0.0 |
| AdrX + CGP20712A + tyramine | 7 | 15.2 ± 4.9‡ | 0.0 ± 0.0 | 7 | 22.5 ± 2.0‡ | 0.1 ± 0.0 |
| AdrX + ICI-118551 + tyramine | 7 | 15.3 ± 1.6‡ | 0.0 ± 0.0 | 9 | 22.7 ± 2.5‡ | 0.4 ± 0.2 |
| AdrX + nadolol + tyramine | 8 | 11.6 ± 1.9‡‡ | 0.0 ± 0.0 | 11 | 21.0 ± 2.8‡ | 0.2 ± 0.2 |
| PROTOCOL 3: ROLE OF ADRENAL NICOTINIC RECEPTORS AND GANGLION TRANSMISSION IN β1AR MODULATION OF CATECHOLAMINE RELEASE | ||||||
| Hexamethonium + tyramine (nicotinic receptor ant.) | 6 | 26.1 ± 1.4† | 0.6 ± 0.3† | 6 | 19.6 ± 0.9†† | 1.7 ± 0.5†† |
| AdrX + hexamethonium + tyramine | 6 | 23.0 ± 1.3 | 0.4 ± 0.3 | 9 | 62.1 ± 9.0§§ | 0.6 ± 0.4 |
| AdrX + hexamethonium + atenolol + tyramine | 6 | 12.5 ± 0.6‡‡ | 0.6 ± 0.6 | 6 | 37.9 ± 5.0‡ | 0.6 ± 0.6 |
| PROTOCOL 4: ROLE OF THE RENIN-ANGIOTENSIN SYSTEM AND THE KIDNEYS IN β1AR MODULATION OF CATECHOLAMINE RELEASE | ||||||
| Losartan + tyramine (angiotensin AT1 receptor ant.) | 9a | 18.4 ± 0.7† | 4.2 ± 1.5 | 6a | 28.4 ± 3.4 | 11.8 ± 4.1 |
| Losartan + atenolol + tyramine | 6 | 12.4 ± 0.9‡‡ | 1.4 ± 0.2 | 6 | 17.1 ± 1.7‡ | 7.1 ± 1.6 |
| Losartan + metoprolol + tyramine | 6 | 10.5 ± 0.5‡‡ | 2.8 ± 0.5 | 6 | 15.1 ± 1.5‡ | 11.9 ± 2.6 |
| AdrX + losartan + tyramine | 7 | 19.3 ± 2.0 | 0.2 ± 0.1§ | 12 | 35.6 ± 4.7 | 0.2 ± 0.0§§ |
| AdrX + losartan + atenolol + tyramine | 7 | 13.4 ± 0.7‡ | 0.7 ± 0.7§ | 6 | 47.5 ± 6.0§§ | 0.0 ± 0.0§§ |
| NX + PBS + tyramine | 7 | 33.9 ± 1.6†† | 16.1 ± 4.0† | 6 | 34.2 ± 2.5† | 8.2 ± 1.1 |
| NX + atenolol + tyramine | 6 | 24.6 ± 1.4‡‡ | 4.7 ± 1.0‡ | 6 | 25.2 ± 2.9‡ | 7.0 ± 1.4 |
Comparisons were made between the SHR and WKY control groups (* after SHR values). Within each strain, comparisons were made between the PBS + tyramine control groups and the groups pre-treated with hexamethonium, losartan, or NX alone (†), between corresponding groups without or with pre-treatment with βAR antagonist (‡) and corresponding groups without or with AdrX (§). Differences were detected as indicated.
N, number of rats per group. Ant., antagonist.
aFrom Ref. (11). †, ‡, § – P ≤ 0.05, **, ††, ‡‡, §§ – P ≤ 0.005.