[Effect of water immersion on levels of atrial natriuretic peptide in patients with chronic renal failure].

An effect of a 2-hour water immersion on the blood serum ANP was investigated in 20 haemodialysed patients with chronic renal failure and in 15 healthy individuals. Water immersion produced an increase in volume in both healthy individuals and the patients of similar degree. Baseline ANP concentration (290.0 +/- 21.9 pg/mL) was significantly higher in the dialysed patients than that in healthy individuals (66.0 +/- 5.5 pg/mL). Water immersion decreased mean arterial pressure (previously significantly higher in the patients) in both healthy individuals and examined patients, significantly increased secretory renal function (significantly higher in healthy individuals than in the examined patients), and increased ANP (previously significantly higher in healthy subjects). A significant correlation between ANP level in blood serum and changes in volume was seen only in healthy individuals. The obtained results suggest a contribution of other than changed volume factors of ANP release regulation and other than ANP factors to pathomechanism of post-immersion drop of the arteria blood pressure and increased secretory renal function in both healthy individuals and patients with renal failure.