randomised placebo-controlled cross-over study

Kim van der Zander, Alphons J.H.M. Houben, Leo Hofstra, Abraham A. Kroon, and Peter W. de Leeuw. Objective: Brain natriuretic peptide (BNP) is a cardiac hormone with natriuretic activity. The aim of the present study was to investigate the cardiovascular effects of pathophysiological levels of BNP on central hemodynamics, cardiac function, renal hemodynamics and function, and microvascular hemodynamics in healthy subjects. Methods: In this double blind, placebo-controlled, cross-over study we infused BNP (4 pmol/kg/min) or placebo (i.v.) for 1 hour, on two separate days, in 12 healthy subjects (mean age 60±5yr.). Nailfold and conjunctival capillary density, finger skin (thermoregulatory) microvascular blood flow (SBF), and cardiac output, were studied before and after infusion, using intravital videomicroscopy, laser-Doppler fluximetry, and echocardiography respectively. Furthermore, during infusion we measured effective renal plasma flow (ERPF), and glomerular filtration rate (GFR) using PAH/inulin clearance. Blood pressure and heart rate (HR) were monitored at all measurements. Results: Compared to placebo, BNP significantly decreased stroke volume with