“Collectively, these experimental results suggest that losartan at low concentrations inhibits the CA secretion evoked by cholinergic stimulation (both nicotininc and muscarinic receptors) as well as by membrane depolarization from the rat adrenal medulla, but at high concentration it rather inhibits ACh-evoked CA secretion.”
“Furthermore, in … with losartan (15 microM) …, the CA secretory responses evoked by Bay-K-8644 (10 microM, an activator of L-type Ca(2+) channels), cyclopiazonic acid (10 microM, … cytoplasmic Ca(2+)-ATPase), veratridine (100 microM, an activator of Na(+) channels), and Ang II (100 nM) were markedly inhibited.”
“However, at high concentrations (150~300 microM), losartan rather enhanced the CA secretion evoked by ACh.”
“ Losartan (5~50 microM) perfused into an adrenal vein for 90 min produced dose- and time-dependent inhibition of the CA secretory responses evoked by ACh (5.32 mM), high K(+) (56 mM, a direct membrane depolarizer), DMPP (100 microM) and McN-A-343 (100 microM).”