Clinical Neuroscience

[CENTRAL ATRIAL NATRIURETIC PEPTIDE IN DEHYDRATION]

BAHNER Udo1, GEIGER Helmut2, PALKOVITS Miklós3, LENKEI Zsolt3, LUFT C. Friedrich4, HEIDLAND August1

MARCH 20, 2007

Clinical Neuroscience - 2007;60(03-04)

[To test the effect of dehydration on brain atrial natriuretic peptide (ANP) concentrations in areas important to salt appetite, water balance and cardiovascular regulation, we subjected rats to dehydration and rehydration and measured ANP concentration in 18 brain areas, as well as all relevant peripheral parameters. Water deprivation decreased body weight, blood pressure, urine volume, and plasma ANP, while it increased urine and plasma osmolality, angiotensin II, and vasopressin. ANP greatly increased in 17 and 18 brain areas (all cut cerebral cortex) by 24 h. Rehydration for 12 h corrected all changes evoked by dehydration, including elevated ANP levels in brain. We conclude that chronic dehydration results in increased ANP in brain areas important to salt appetite and water balance. These results support a role for ANP as a neuroregulatory substance that participates in salt and water balance.]

AFFILIATIONS

  1. KfH Nierenzentrum, Würzburg
  2. Department of Internal Medicine-Nephrology, University of Frankfurt, Frankfurt/Main
  3. Neuromorphological and Neuroendocrine Research Laboratory, Hungarian Academy of Sciences and Semmelweis University, Budapest
  4. Department of Internal Medicine-Nephrology and Hypertension, Franz-Volhard-Klinik at the MDC, Berlin

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