Influence of Circulating Epinephrine and Norepinephrine on Insulin-Like Growth Factor Binding Protein-1 in Humans

Abstract

The aim of the present study was to investigate the influence of circulating epinephrine (Epi) and norepinephrine (Norepi) on serum insulin-like growth factor binding protein-1 (IGFBP-1) concentrations. Healthy men received 0.3 nmol·kg·min Epi iv (n = 6), 0.5 nmol·kg·min Norepi iv (n = 7), or saline (n= 5) during 30 min. Arterial blood samples were obtained before, during, and 120 min after infusion. During the catecholamine infusion arterial Epi and Norepi plasma concentrations reached 6.35 ± 0.53 and 15.65 ± 2.71 nmol/L, respectively, which resulted in significant increases in glucose concentrations. When Epi was infused, IGFBP-1 increased from 45 ± 6 μg/L to 76 ± 10 μg/L (P < 0.05) 60 min after the infusion. Epi was also followed by increases in insulin, C-peptide, and glucagon. Norepi resulted in a slight increase in circulating IGFBP-1 (43 ± 6 to 54 ± 8 nmol/L, NS). The findings suggest that Epi, at plasma concentrations similar to those reached during physical stress, stimulates the production of IGFBP-1 in humans.