title: Does brain natriuretic peptide have a direct renal effect in human hypertensives?
abstract: Systemic infusion of brain natriuretic peptide (BNP) stimulates natriuresis and diuresis but has variable effects on the renal vasculature. In this study, we investigated whether BNP has any direct effects on the kidney in hypertensive patients. Three stepwise increasing doses of BNP (60, 120, and 180 pmol/min) or placebo were infused into the renal artery of 26 hypertensive patients. Renal blood flow was determined with the 133Xenon washout technique. Before and after infusion of BNP, arterial and venous blood samples were taken for cGMP, renin, and creatinine concentration. Intra-arterial blood pressure and heart rate were monitored continuously. Intrarenal BNP infusion did not induce significant changes in renal blood flow despite increases in circulating levels of cGMP. The latter, however, was not associated with changes in the cGMP gradient across the kidney. In addition, we did not find any BNP-related changes in the secretion of active renin and in creatinine extraction. At the highest dose, heart rate increased after BNP infusion without a change in mean intra-arterial blood pressure. In conclusion, this study suggests that at least in hypertensive subjects, BNP has no direct intrarenal hemodynamic effects and that the rise in circulating cGMP without changes in net renal extraction of this second messenger is related to a primary extrarenal target of BNP.
authors.affiliation: Department of Medicine, Cardiovascular Research Institute Maastricht, and University Hospital Maastricht, The Netherlands.
authors.forename: Kim
authors.initials: K
authors.lastname: van der Zander
authors.forename: Alphons J H M
authors.initials: AJ
authors.lastname: Houben
authors.forename: Abraham A
authors.initials: AA
authors.lastname: Kroon
authors.forename: Thomas K A
authors.initials: TK
authors.lastname: Wierema
authors.forename: Monique J M J
authors.initials: MJ
authors.lastname: Fuss-Lejeune
authors.forename: Derk
authors.initials: D
authors.lastname: Koster
authors.forename: Peter W
authors.initials: PW
authors.lastname: de Leeuw
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D003404:Creatinine / Q000097:blood; D006152:Cyclic GMP / Q000097:blood; D004305:Dose-Response Relationship, Drug; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006978:Hypertension, Renovascular / Q000097:blood / Q000503:physiopathology*; D007261:Infusions, Intra-Arterial; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D012077:Renal Artery / Q000187:drug effects / Q000503:physiopathology; D012079:Renal Circulation / Q000187:drug effects*; D012083:Renin / Q000097:blood
chemical_list: D020097:Natriuretic Peptide, Brain; D003404:Creatinine; D012083:Renin; D006152:Cyclic GMP