Urinary Cyclic Adenosine Monophosphate Excretion in Diabetes Insipidus of Childhood Effect of Vasopressin and Chlorpropamide

Abstract

Excretion of urinary cyclic AMP (cAMP) was determined in 7 children suffering from central diabetes insipidus (CDI), 3 children suffering from nephrogenic diabetes insipidus (NDI), and 5 normal children. Excretion of cAMP was found to be depressed in both types of DI. Administration of long-acting vasopressin in physiologically effective dosage (ADH, 5.1 U per 1.7 m2) decreased the absolute rate of cAMP excretion slightly in reference and CDI children, but had no effect on NDI children. Infusion of large doses of ADH (600 mU per 1.7 m2 per h) into CDI children also reduced cAMP excretion slightly, but in relation to creatinine excretion, an increase of about 30 per cent was found. This increase of the cAMP/creatinine ratio was due to a greater decrease in creatinine than in cAMP excretion. Chlorpropamide had no effect on cAMP excretion in CDI patients.