To determine the effects of stress hormones on insulin-like growth factor 1 (IGF-1).
Insulin induced hypoglycemia (< 3 mmol/l) and clonidine induced depression of noradrenergic tone were used to assess the acute effects of cortisol, human growth hormone (hGH), and norepinephrine (NE).
Despite the increase of hGH during hypoglycemia, a statistically significant decrease of IGF-1 was observed along with the expected rise of cortisol and NE. To eliminate the role played by NE, NE tone was depressed by administering clonidine. A statistically significant decrease of IGF-1 was also observed.
Acute cortisol release or a NE decrease induce low IGF-1 levels.