Effect of angiotensin II and atrial natriuretic factor on neurons in the subfornical organ of ducks and rats in vitro.

Atrial natriuretic factor (ANF) antagonizes many angiotensin II (ANGII)-induced effects on osmoregulatory relevant parameters in vivo. In this study ANF analogues decreased the spontaneous and the ANGII-induced electrical activity of subfornical organ (SFO) neurons in rats, but had no effect on ANGII sensitive or insensitive SFO neurons in ducks. These results suggest a more distinct functional separation for the responsiveness to ANGII and ANF in birds compared to mammals.