Korean J Obstet Gynecol.  2000 Mar;43(3):488-496.

The levels of insulin-like growth factor-binding proteins and their protease activity in serum and follicular fluid during the controlled ovarian hyperstimulation cycle

• Kim JG
• Suh CS
• Kim SH
• Choi YM
• Moon SY
• Lee YH
• Lee JY

Abstract

OBJECTIVES
To evaluate changes in serum insulin-like growth factor binding protein(IGFBP)s profiles during the controlled hyperstimulation cycle and to compare IGFBPs profiles and their protease activity in follicular fluid(FF) from polycystic ovary and preovulatory follicle containing mature oocyte.
METHODS
IGFBPs and their protease activity were measured by western ligand blot, immunoprecipitation and mixing test in fasting blood samples obtained throughout ovarian hyperstimulation cycle from 33 patients undergoing in vitro fertilization (IVF)-embryo transfer, and in FF from polycystic ovary(n=10) and IVF follicle(n=30) containing mature oocyte. Serum 17 -estradiol was also determined by radioimmunoassay.
RESULTS
Type and molecular weight of serum IGFBP did not changed during the controlled hyperstimulation cycle. No significant variations in the relative proportion, level of IGFBPs and their protease activity were found throughout the stimulated cycle. IGFBP-4 levels in FF from polycystic ovary were significantly higher than in FF from IVF follicle and IGFBP -2 levels also showed a similar trend, but no significant differences in other IGFBP profiles and their protease activity were noted. IGFBP-4 protease activity was significantly higher in the latter follicle than in the former follicle. There were significant correlations between serum IGFBP-1, IGFBP-3 and 17 -estradiol levels. Correlation between serum and FF IGFBP except IGFBP-1 was not significant.
CONCLUSIONS
IGFBPs have regulatory functions in ovary through an paracrine and autocrine rather than endocrine mechanism during the controlled hyperstimulation cycle. IGFBP-4 and its protease activity in FF may be involved in the follicle growth.

Keyword

Hyperstimulation cycle; Follicular fluid; IGFBP; Protease; Follicle growth

MeSH Terms

Fasting
Female
Fertilization in Vitro
Follicular Fluid*
Humans
Immunoprecipitation
Insulin-Like Growth Factor Binding Protein 1
Insulin-Like Growth Factor Binding Protein 3
Insulin-Like Growth Factor Binding Protein 4
Insulin-Like Growth Factor Binding Proteins
Molecular Weight
Oocytes
Ovary
Pregnancy-Associated Plasma Protein-A
Radioimmunoassay
Insulin-Like Growth Factor Binding Protein 1
Insulin-Like Growth Factor Binding Protein 3
Insulin-Like Growth Factor Binding Protein 4
Insulin-Like Growth Factor Binding Proteins
Pregnancy-Associated Plasma Protein-A