The haemodynamic, renal and endocrine effects of alpha-human atrial natriuretic polypeptide in normotensive people and patients with essential hypertension.
Intravenous administration of a small dose of synthetic alpha-human atrial natriuretic polypeptide (alpha-hANP, 0.025 microgram/kg per min) decreased arterial pressure and total peripheral resistance to a similar extent in eight normotensive people and 11 untreated patients with essential hypertension. Cardiac output was slightly, but not significantly, increased in both groups. Urinary volume, urinary sodium excretion and glomerular filtration rate (GFR) were significantly increased only in the hypertensives. However, net tubular reabsorption of sodium was enhanced in the hypertensives. Haematocrit (Ht) was increased in both groups. Although plasma renin activity (PRA) did not change in either group, plasma aldosterone was significantly decreased in the groups, with a greater change in the normotensives. These findings indicate that the hypotensive effect of alpha-hANP is due to the dilatation of resistant vessels, and that an increase in GFR, probably brought about by the combination of an increase in vascular permeability (as suggested by the changes in Ht) and high arterial pressure, is one of the main factors leading to the diuresis and natriuresis induced by alpha-hANP.
D000328:Adult; D009320:Atrial Natriuretic Factor / Q000097:blood / Q000494:pharmacology*; D004702:Endocrine Glands / Q000187:drug effects*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D006973:Hypertension / Q000503:physiopathology*; D007668:Kidney / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D012016:Reference Values
D009320:Atrial Natriuretic Factor