EVIDENCE THAT THE ANTIDIURETIC SUBSTANCE IN THE PLASMA OF CHILDREN WITH NEPHROGENIC DIABETES INSIPIDUS IS ANTIDIURETIC HORMONE

Abstract

The antidiuretic activity in the plasma of four children with nephrogenic diabetes insipidus was measured by a rat assay technique. The evidence presented to indicate that this activity was due to antidiuretic hormone (ADH) was as follows: (a) the activity was higher in jugular vein plasma than in femoral or antecubital vein plasma, (b) it was high when the children were thirsted and decreased when they drank water, (c) it was destroyed when the plasma was incubated with thioglycollate, and (d) it was ultrafilterable, and vasopressin (Pitressin), when injected, was distributed as though it was ultrafilterable. When the children were given vasopressin, there was no change in urine flow or osmolality, but plasma antidiuretic activity was higher than it was when water deprivation led to a reduction in urine flow and an increase in urine osmolality. The inference of these findings is that ADH is secreted normally in children with nephrogenic diabetes insipidus, it is ultrafilterable, but it is not a factor in modifying urine flow in response to dehydration.