Water immersion induced alterations of plasma vasopressin levels and activity of the renin-angiotensin-aldosterone system in noninflammatory acute renal failure and end-stage renal failure.

UNLABELLED

Water immersion (WI) induced alterations of plasma renin activity (PRA), plasma aldosterone (Aldo), vasopressin (AVP), sodium and potassium concentrations and plasma volume (PV) were examined in 12 patients with noninflammatory acute renal failure (NARF) in the anuric/oliguric phase, in 20 patients with chronic renal failure (CRF) and in 15 healthy subjects. In all examined groups a significant increase of PV and decrease of PRA, plasma Aldo, AVP after WI were observed. Significantly more marked decreases of PRA were observed in patients with NARF than in those with CRF and in healthy subjects. In patients with NARF the increase of PV was significantly greater than in CRF and in healthy subjects. In patients with NARF a significantly more marked decrease of plasma sodium concentration was also noted after WI than in subjects with CRF and in normals. Only in healthy subjects was a significant negative correlation noted between the WI increase of PV and decrease of plasma AVP level. In healthy subjects, significantly positive correlations were noted between WI induced decrease of PRA and Aldo and between PRA and plasma AVP, respectively. Such correlations were absent in uraemic patients.

IN CONCLUSION

(1) patients with CRF and NARF show similar, but quantitatively different responses of PRA, Aldo and AVP secretion to WI as compared with normals; (2) patients with NARF and CRF are characterized by an inappropriate volumetric and osmotic regulation of AVP secretion; (3) in uraemic patients the physiological relationship between the renin-angiotensin system and AVP secretion seems to be dissociated.