Adrenergic and osmotic responses to atrial natriuretic peptide and angiotensin II in the duck (Anas platyrhynchos)

There is evidence that analogues of atrial natriuretic peptide (ANP) and angiotensin II (ANG II) occur in birds. The present experiments studied the adrenergic and osmoregulatory responses to synthetic ANP and ANG II in salt-loaded ducks (Anas platyrhynchos). Excretion of water and salt through the nasal salt glands was abolished by ANG II. This extrarenal, salt-retaining effect of ANG II was not altered by ANP. However, ANP did augment the diuretic response to ANG II. ANP also potentiated the stimulatory effect of ANG II on plasma norepinephrine. The data are consistent with physiological roles for native analogues of ANP and ANG II in adrenergic and osmotic regulation in the duck.