Table 3.
Effect of low-dose Ang II combined with regular or 2% high salt diet on brain and plasma aldosterone and corticosterone and adrenal CYP11B1 expression (top panel); and effect of central MR-ENaC-AT1R blockade on plasma aldosterone and corticosterone (bottom panel)
| Regular salt | High salt | Regular salt + Ang II | High salt + Ang II | |
|---|---|---|---|---|
| Brain aldosterone (pg/g) | ||||
| Hypothalamus | 69 ± 20 | 101 ± 34 | 135 ± 19 | 295 ± 79* |
| Hippocampus | 53 ± 9 | 63 ± 16 | 113 ± 21 | 211 ± 39* |
| Brain corticosterone | ||||
| (ng/g) | ||||
| Hypothalamus | 3.1 ± 0.7 | 9.4 ± 4.7 | 8.0 ± 2.1 | 36.8 ± 11.4* |
| Hippocampus | 3.7 ± 0.9 | 8.5 ± 3.6 | 8.6 ± 2.3 | 32.9 ± 7.6* |
| Plasma aldosterone | 91 ± 15 | 90 ± 21 | 206 ± 42 | 383 ± 100* |
| (pg/ml) | ||||
| Plasma corticosterone | 98 ± 25 | 115 ± 32 | 75 ± 27 | 198 ± 43* |
| (ng/ml) | ||||
| Adrenal cortex CYP11B1 | ||||
| mRNA (CYP11B1/PGK1) | 5.9 ± 0.6 | 6.7 ± 0.3 | 5.7 ± 0.3 | 6.3 ± 0.5 |
| Protein (CYP11B1/β-actin) | 1.9 ± 0.3 | 2.1 ± 0.4 | 1.8 ± 0.5 | 1.2 ± 0.1 |
| High salt + Ang II | ||||
| + | + | + | + | |
| Veh (n = 11) | MR inh (n = 9) | Ben (n = 6) | Los (n = 4) | |
| Plasma aldosterone (pg/ml) | 179 ± 84* | 41 ± 9 | 69 ± 31 | 44 ± 13 |
| Plasma corticosterone (ng/ml) | 108 ± 35 | 72 ± 24 | 113 ± 57 | 53 ± 17 |
Values are means ± SE.
Top panel: Values for hypothalamus and hippocampus aldosterone and corticosterone, n = 6–8/group (second study of first experiment); for plasma aldosterone, n = 12–16/group for two studies combined; for plasma corticosterone, n = 8–12/group (preliminary experiment + first study of first experiment); for CYP11B1/PGK1, n = 11–14/group (two studies combined), and for CYP11B1/β-actin, n = 5–6/group (second study of first experiment).
Lower panel: Values for plasma aldosterone and corticosterone for vehicles (Veh), combined eplerenone and spironolactone (MR inh), benzamil (Ben) and losartan (Los).
P < 0.05 vs. others.