title: Renal effects of atrial natriuretic factor are independent of dopamine1 receptors.
abstract: This study examined whether the renal effects of atrial natriuretic factor (ANF) are mediated by dopamine1 (DA1) receptor activation. Intravenous infusion of low-dose ANF (0.0025 micrograms.kg-1.min-1) in euvolemic, pentobarbital sodium-anesthetized male mongrel dogs enhanced urine flow (V) by 71 +/- 14% (mean +/- SE) and urinary sodium excretion (UNaV) by 457 +/- 172% (P less than 0.05). Renal blood flow (RBF) was unchanged. Administration of pharmacological doses of ANF (0.1 microgram.kg-1.min-1) into the renal artery in volume-expanded dogs increased RBF by 26 +/- 6, V by 56 +/- 15, and UNaV by 101 +/- 42%. The selective DA1 receptor antagonist SCH-23390 (0.5 microgram.kg-1.min-1 iv) did not affect the response to ANF at either dose. The selective DA1 agonist, fenoldopam, increased RBF by 45 +/- 3, V by 94 +/- 27, and UNaV by 61 +/- 15% in volume-expanded dogs. With SCH-23390, fenoldopam increased RBF by only 16 +/- 6% whereas V and UNaV decreased by 16 +/- 10 and 17 +/- 10%, respectively. Accordingly, the failure of DA1 receptor-blocking doses of SCH-23390 to antagonize the response to ANF, at pharmacological or physiological doses, indicates that the renal effects of ANF, in the dog, are independent of DA1 receptor activation.
authors.affiliation: Department of Pharmacological and Physiological Sciences, University of Chicago, Illinois 60637.
authors.forename: M B
authors.initials: MB
authors.lastname: Murphy
authors.forename: A S
authors.initials: AS
authors.lastname: Bass
authors.forename: L I
authors.initials: LI
authors.lastname: Goldberg
mesh_terms: D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D001552:Benzazepines / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D004285:Dogs; D018492:Dopamine Antagonists; D004305:Dose-Response Relationship, Drug; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D007668:Kidney / Q000187:drug effects / Q000502:physiology*; D008297:Male; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology*; D017447:Receptors, Dopamine D1; D012016:Reference Values; D012079:Renal Circulation / Q000187:drug effects; D012964:Sodium / Q000652:urine
chemical_list: D001552:Benzazepines; D018492:Dopamine Antagonists; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D009320:Atrial Natriuretic Factor; D012964:Sodium