title: Arginine vasopressin and the renal response to water loading in congestive heart failure.
abstract: Previous studies have shown on the basis of isolated comparisons that plasma arginine vasopressin (AVP) levels are inappropriately increased for a given serum osmolality in patients with CHF. To explore further the osmoregulation of AVP in this condition, the response of plasma AVP to a 15- to 20-ml/kg oral water load was compared in 26 patients with CHF and 14 normal subjects. In the normal subjects, serum osmolality decreased from 289 +/- 5.0 to 282 +/- 5.0 mOsm/kg (p less than 0.001) and AVP from 3.6 +/- 1.1 to 2.1 +/- 0.78 pg/ml (p less than 0.001). In the patients with CHF, osmolality decreased from 289 +/- 7.0 to to 281 +/- 7.0 mOsm/kg and AVP from 7.1 +/- 3.6 to 5.8 +/- 3.4 pg/ml (p less than 0.001). As a percentage of the control value, the decrease in AVP was much greater in the normal group, 41 +/- 15% vs 18 +/- 10% (p less than 0.001). Urinary osmolality levels were measured before and after water loading in 11 patients and in 7 normal subjects. Normal subjects diluted from 812 +/- 130 to 133 +/- 26 mOsm/kg (p less than 0.001) and CHF patients from 599 +/- 218 to 253 +/- 170 mOsm/kg, a statistically significant (p less than 0.01) but smaller (p less than 0.05) level of suppression. There were, however, 2 distinct groups within the CHF population: one in which urine osmolality was appropriately decreased (from 594 +/- 269 to 144 +/- 37 mOsm/kg, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000328:Adult; D000368:Aged; D001127:Arginine Vasopressin / Q000097:blood*; D001769:Blood; D005260:Female; D006333:Heart Failure / Q000503:physiopathology*; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D014556:Urine; D014867:Water; D014882:Water-Electrolyte Balance
chemical_list: D014867:Water; D001127:Arginine Vasopressin