Human Growth Hormone Release in Sleep: Nonsuppression by Acute Hyperglycemia¹

Abstract

After 2 base line study nights, hyperglycemia of 43–348% above base line was achieved during early sleep on a third night by constant glucose infusion in 6 normal young men. No significant difference in human growth hormone (HGH) release in sleep occurred between base line (mean peak HGH ±se 17.1±2.9 ng/ml) and infusion nights (13.9±4.2 ng/ml). Thus, release of HGH in sleep is not suppressed by acute hyperglycemia. This suggests sleep release is not a substrate servorhythm comparable to waking HGH release. It may be a primary neural rhythm perhaps facilitating protein synthesis.