Inhibin B, Follicle Stimulating Hormone, Luteinizing
Hormone, and Estradiol and Their Relationship to the Regulation
of Follicle Development in Girls during Childhood And Puberty
M. CHADA, R. PRŮŠA, J.
BRONSKÝ, M. PECHOVÁ, K. KOTAŠKA, L. LISÁ1
Department of Clinical Biochemistry and Pathobiochemistry
and 1First Pediatric Department, Second Faculty
of Medicine, Charles University, Faculty Hospital Motol,
Prague, Czech Republic
Received April 5, 2002
Accepted June 24, 2002
Summary
Inhibin B, produced by granulosa cells in the ovary, is a
heterodimeric glycoprotein suppressing synthesis and secretion
of the follicle stimulating hormone (FSH). The aim of the
present study was to determine hormone profiles of inhibin B,
FSH, luteinizing hormone (LH), and estradiol in girls during
childhood and puberty and to evaluate whether inhibin B is a
marker of follicle development. We examined the correlation
between inhibin B and gonadotropins and estradiol during the
first two years and across the pubertal development. Using a
specific two-side enzyme-linked immunosorbent assay (ELISA),
inhibin B levels were measured in the serum of 53 healthy girls
divided into 8 groups according to age. In addition, serum FSH,
LH, and estradiol were measured by chemiluminescent immunoassay
in all serum samples. A rise in serum levels of inhibin B
(55.2±7.3 ng/l, mean ± S.E.M.) and FSH (1.78±0.26 UI/l),
concomitant with a moderate increment of serum LH (0.36±0.09
UI/l) and estradiol (45.8±12.2 pmol/l) concentrations was
observed during the first three months of life and declined to
prepubertal concentrations thereafter. A strong positive
correlation between inhibin B and FSH (r = 0.48, p<0.05), LH (r
= 0.68, p<0.001) and estradiol (r = 0.59, p<0.01) was
demonstrated during the first 2 years of life. A rise in serum
levels of inhibin B, FSH, LH, and estradiol was found throughout
puberty. Inhibin B had a strong positive correlation with FSH
(stage I of puberty: r = 0.64, p<0.05; stage II of puberty: r =
0.86, p<0.01), LH (I: r = 0.61, p<0.05; II: r = 0.67, p<0.05),
and estradiol (II: r = 0.62, p<0.05) in early puberty. From
pubertal stage II, inhibin B lost this relationship to
gonadotropins and estradiol. Serum inhibin B and FSH levels
increased significantly during pubertal development, with the
highest peak found in stage III of puberty (133.5±14.3 ng/l),
and decreased thereafter. In conclusion, inhibin B is produced
in a specific pattern in response to gonadotropin stimulation
and plays an important role in the regulation of the
hypothalamic-pituitary-gonadal axis during childhood and puberty
in girls. Inhibin B is involved in regulatory functions in
developing follicles and seems to be a sensitive marker of
ovarian follicle development.
Key
words
Inhibin B • Girl • Childhood • Puberty
Reprint
requests
MUDr. Martin Chada, Department of Clinical Biochemistry and
Pathobiochemistry, Second Faculty of Medicine, Charles
University, Faculty Hospital Motol, V Úvalu 84, 150 06 Prague 5,
The Czech Republic, Fax: +420 2 2443 5320,
E-mail:
martinchada@hotmail.com
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