Dissociation of Prolactin Response to Thyrotropin- Releasing Hormone and Metoclopramide in Chronic Renal Failure*

Abstract
PRL [prolactin] secretion was evaluated in 14 males with chronic renal failure on long term hemodialysis. Twelve had basal hyperprolactinemia. Ten subjects were challenged with TRH [thyrotropin-releasing hormone] in doses ranging from 200-1000 .mu.g. None responded to 200 or 500 .mu.g TRH, although 2 of 4 subjects tested did respond to 1000 .mu.g TRH. All 4 subjects challenged with metoclopramide had PRL responses which were indistinguishable from those of the controls. There is a dissociation in responsiveness to metoclopramide and TRH in chronic renal failure.