Inhibition of vasopressin and aldosterone release by atrial natriuretic peptide in conscious rabbits.
To elucidate the regulatory role of atrial natriuretic factor (ANF) on vasopressin (AVP) and aldosterone release in conscious rabbits, ANF was administered systematically at a rate of 15 pmol min-1 (kg body wt)-1 for 15 min in two series of experimental animals in which AVP and/or aldosterone production was stimulated. In euhydrated rabbits (series I), systemic administration of angiotensin II (Ang II) (10 pmol min-1 (kg body wt)-1, 15 min) stimulated aldosterone release threefold from basal plasma concentrations (140 pg ml-1). The co-application of ANF inhibited the Ang II-induced release of aldosterone without influencing the non-stimulated AVP system. In dehydrated rabbits (series II) with elevated plasma osmolality and AVP concentration, exogenously applied ANF increased plasma ANF fourfold at marginally reduced arterial pressure. Plasma AVP concentrations were reduced by 3.4 pg ml-1 (25%) on average, and plasma aldosterone concentrations were lowered by 34 pg ml-1 (23%) at unchanged levels of plasma corticosterone. Receptor binding studies using [125I]ANF as radioligand revealed Ang II-independent high-affinity receptors for ANF in the zona glomerulosa of the adrenal gland. With regard to the hypothalamo-neurohypophyseal AVP system, ANF binding sites were localized to the median eminence and neurohypophysis, but not to the magnocellular nuclei. ANF receptors were also labelled in structures lacking a blood-brain barrier such as the subfornical organ and the choroid plexus.
Gerstberger
R
R
Max-Planck-Institute for Physiological and Clinical Research, W.G. Kerckhoff-Institute, Bad Nauheim, FRG.
Schütz
H
H
Luther-Dyroff
D
D
Keil
R
R
Simon
E
E
D000311:Adrenal Glands / Q000378:metabolism; D000450:Aldosterone / Q000378:metabolism; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001127:Arginine Vasopressin / Q000037:antagonists & inhibitors* / Q000378:metabolism; D009320:Atrial Natriuretic Factor / Q000097:blood / Q000494:pharmacology*; D001665:Binding Sites; D002682:Chinchilla / Q000235:genetics; D003681:Dehydration / Q000097:blood; D005260:Female; D006824:Hybridization, Genetic; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism; D000451:Mineralocorticoid Receptor Antagonists / Q000494:pharmacology*; D010904:Pituitary Gland, Posterior / Q000378:metabolism; D011817:Rabbits
D000451:Mineralocorticoid Receptor Antagonists; D000804:Angiotensin II; D001127:Arginine Vasopressin; D000450:Aldosterone; D009320:Atrial Natriuretic Factor