[Effect of various doses of biosynthetic growth hormone on levels of IGF-I binding protein 3 (IGFBP-3) in patients with hypopituitarism and growth hormone deficiency].
OBJECTIVE
To study the effect of different doses of hGH (biosynthetic human growth hormone--Humatrope) administration on the profile of IGFBP-3 in hypopituitary patients with GHD and to find out the extent of production of IGFBP-3 proteases, which results in the elevated biological IGF-I activity.


METHODS
Ten patients (after 1. collection) were randomized according to the dose of hGH, administered within three months, into group I: 3 micrograms/kg/day and group II: 6 micrograms/kg/day. After 2. collection the doses of hGH were in both groups duplicated and administered another three months (3. collection).


METHODS
RIA's were used to analyse GH, IGF-I, total IGFBP-3 and fIGF-I. The profile of IGFBP-3 forms was studied by electrophoresis with western immunoblotting.


RESULTS
Anabolic effect of administered hGH was demonstrated by significant increase of IGF-I and total IGFBP-3 in both groups of patients. It was evident that this increase is associated with the raise of proteolytic fragment of IGFBP-3 (29 kD).


CONCLUSIONS
The increased doses of hGH change the profile of IGFBP-3 in the sense of increasing concentrations of IGFBP-3 (29 kD). As proteolytic clipping of intact IGFBP-3 is associated with the raise of fIGF-I levels in individual patients it is possible to consider 29 kD IGFBP-3 as the marker of the therapy of hGH in our study. However, the increasing tendency to fIGF-I production after 2-fold higher administration of hGH in majority of patients in the trial is not in average significant so it means that the doses of hGH administered to each individual should be optimalized.
Justová
V
V
Laborator pro endokrinologii a metabolismus III. interní kliniky, 1. lékarská fakulta Univerzity Karlovy, U nemocnice 2, 128 08 Praha 2, Czech Republic.
Lacinová
Z
Z
Marek
J
J
D000328:Adult; D015153:Blotting, Western; D005260:Female; D013006:Growth Hormone / Q000097:blood / Q000172:deficiency*; D019382:Human Growth Hormone / Q000008:administration & dosage*; D006801:Humans; D007018:Hypopituitarism / Q000097:blood* / Q000188:drug therapy; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay
D018972:Insulin-Like Growth Factor Binding Protein 3; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone
Vliv podávání různých dávek biosyntetického růstového hormonu na profil vazebných proteinů 3 pro IGF-I (IGFBP-3) u hypopituitárních pacientů s nedostatecností růstového hormonu.