PULSATILE RELEASE OF ARGININE-VASOPRESSIN (AVP) AND ITS EFFECT ON RESPONSE TO DESMOPRESSIN IN ENURESIS

A response to desmopressin spray is only seen in a proportion of child ren with enuresis. To investigate whether response is related to noctu rnal levels of arginine vasopressin (AVP) 35 children with enuresis, a ged 8 to 14 years, had plasma AVP measurements overnight before enteri ng a double blind randomised, placebo controlled crossover study to as sess their response to evening treatment with desmopressin spray. Ther e was no significant difference seen between nocturnal AVP levels obta ined from children who responded to desmopressin and those who did not . Frequent sampling in six children demonstrated a pulsatile pattern o f secretion for AVP. This has implications for studies of nocturnal AV P levels, and questions the validity of using infrequent measurements of AVP to assess it's secretion.