Growth Hormone Responses to Sleep, Insulin Hypoglycaemia and Arginine Infusion

Abstract

This study compares the peak serum growth hormone (GH) concentration during slow wave sleep with the serum GH responses to insulin-induced hypoglycemia and i.v. Arg infusion in 23 children referred because of short stature (20) or precocious puberty (3). Peak serum GH concentration during sleep correlated significantly with peak GH response to insulin hypoglycemia (r = 0.64, P < 0.01) and Arg infusion (r = 0.57, P < 0.01); 3 children had subnormal (< 15 mU/l) peak serum GH concentrations during sleep but normal responses to either insulin-induced hypoglycemia or i.v. Arg infusion. One child had a normal peak serum GH response to sleep but subnormal responses to insulin and Arg. Sleep studies of GH secretion may be indicated when the GH responses to pharmacological stimuli are inconsistent with the observed growth pattern.