HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Skjæbæk, C. Articles by Ørskov, H. Search for Related Content PubMed Articles by Skjæbæk, C. Articles by Ørskov, H.

Free and total insulin-like growth factors and insulin-like growth factor binding proteins during 14 days of growth hormone administration in healthy adults

Skjærbæk C, Frystyk J, Møller J, Christiansen JS, Ørskov H. Free and total insulin-like growth factors and insulin-like growth factor binding proteins during 14 days of growth hormone administration in healthy adults. Eur J Endocrinol 1996;135:672–7. ISSN 0804–4643

The objective was to investigate the effect of growth hormone (GH) administration on circulating levels of free insulin-like growth factors (IGFs) in healthy adults. Eight healthy male subjects were given placebo and two doses of GH (3 and 61U/m² per day) for 14 days in a double-blind crossover study. Fasting blood samples were obtained every second day. Free IGF-I and IGF-II were determined by ultrafiltration of serum. Total IGF-I and IGF-II were measured after acid–ethanol extraction. In addition, GH, insulin, IGF binding protein 1 (IGFBP-1) and IGFBP-3 were measured. Serum-free and total IGF-I increased in a dose-dependent manner during the 14 days of GH administration. After 14 days, serum-free IGF-I values were 610 ± 100 ng/l (mean±SEM) (placebo), 2760 ± 190 ng/l (3IU/m²) and 3720 ± 240 ng/l(6 IU/m²) (p = 0.0001 for 3 and 6 IU/m² vs placebo; p = 0.004 for 3 IU/m² vs 6 IU/m²). Total IGF-I values were 190 ± 10 µg/l (placebo), 525 ± 10 (3 IU/m²), and 655 ± 40 µg/l (6 IU/m²) (p < 0.0001 for 3 and 6IU/m² vs placebo; p = 0.04 for 3 IU/m² vs 6 IU/m²). There were no differences in the levels of free or total IGF-II during the three study periods. Insulin-like growth factor binding protein 1 was decreased during GH administration (p = 0.04 for placebo vs 3IU/m²; p = 0.006 for placebo vs 6 IU/m²). In conclusion, fasting serum free IGF-I increased dose dependently during GH administration and free IGF-I increased relatively more than total IGF-I. This may partly be due to the decrease in IGFBP-1.

Christian Skjærbæk, Institute of Experimental Clinical Research, Medical Research Laboratories, Aarhus Kommune Hospital, Norrebrogade 44, DK-8000 Aarhus C, Denmark