Postprandial natriuresis in humans: further evidence that
urodilatin, not anp, modulates sodium excretion.
Drummer, Christian, Wolfgang Frank, Martina Heer, Wolf-Georg
Forssmann, Rupert Gerzer, and Kenneth Goetz.
Institut f[umlaut]ur Luft- und Raumfahrtmedizin der Deutschen
Forschungsanstalt f[umlaut]ur Luft- und Raumfahrt (DLR), 51140
Cologne; Germany, Nieders[umlaut]achsisches Institut f[umlaut]ur
Peptid-Forschung, 30625 Hannover, Germany
APStracts 2:0159F, 1995.
We examined the effects of a high-salt (100 mmol NaCl) and a low-salt
(5 mmol NaCl) meal on the renal excretion of sodium and chloride in
12 healthy male upright subjects. We also measured the urinary
excretion of urodilatin (ANP-95-126), and the plasma/serum
concentrations of atrial natriuretic peptide (ANP-99-126),
aldosterone and renin. The high-salt meal produced a postprandial
natriuresis (UNaV from 59.0?[mu]mol/min to a peak rate of
204.6?[mu]mol/min in the third hour following ingestion of the meal)
and chloride excretion. In parallel, the urinary excretion of
urodilatin increased from 35.7 fmol/min to a peak rate of 105
fmol/min. The effect of high-salt intake on urinary sodium, chloride
and urodilatin excretion was significant (ANOVA, p<0.01), and
close significant correlations were observed between urodilatin and
sodium excretion (mean R=0.702) as well as between urodilatin and
chloride excretion (mean R=0.776). In contrast, plasma ANP, which was
acutely elevated 15 min following high-salt intake, was already back
to low-salt values one hour later. It did not parallel the
postprandial natriuretic profile and no positive correlation between
plasma ANP and sodium excretion was observed. These results provide
further evidence that urodilatin, not ANP, is the member of this
peptide family primarily involved in the regulation of the excretion
of sodium and chloride.
Received 17 April 1995; accepted in final form 16 August 1995.
APS Manuscript Number F123-5.
Article publication pending Am. J. Physiol. (Renal Fluid Electrolyte
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 23 September 1995.