Selective reduction of adrenal medulla response to angiotensin induced by suppression of renin-angiotensin

Angiotensin II (AII) induced an increase of adrenaline (A) release from rat adrenal glands in vitro. The response of the adrenal glands was completely abolished 22-24 after bilateral nephrectomy. Adrenal glands from DOCA-salt-treated rats did not respond to AII as well, whereas adrenal glands from rats treated with furosemide and a low salt diet retained this response. High potassium in the medium increased significantly the release of A from in vitro incubated adrenal glandsof nephrectomized rats from 0.43 ± 0.04 to 0.63 ± 0.06 μg/gland and salbutamol (in calcium-free medium) increased the release from 0.34 ± 0.03 to 0.43 ± 0.03 μg/gland. These results indicate that the adrenal medulla develops subsensitivity to AII in vitro, following a reduction in levels of this agonist in vivo.