Increase in plasma growth hormone levels following thyrotropin-releasing hormone injection in children with primary hypothyroidism.

Thyrotropin-releasing hormone (TRH) induced a significant increase in plasma growth hormone (GH) levels in 4 of 8 children with primary hypothyroidism, while a slight decrease was observed in 8 control children. Base-line plasma prolactin (PRL) levels and peak responses to TRH were higher in hypothyroid children than in controls. These data may indicate the existence of dysfunction of central nervous system mechanisms of control of GH and PRL secretion in subjects with primary hypothyroidism.