FSH ELISA

Follicle Stimulating hormone (FSH) is a glycoprotein
consisting of two subunits with an approximate
molecular mass of 35,500 daltons. The α- subunit is
similar to other pituitary hormones [luteinizing
stimulating hormone (LH), thyroid stimulating
hormone (TSH) and chorionic gonadotropin (hCG)]
while the β-subunit is unique. The β- subunit confers
the biological activity to the molecule. Stimulation by
gonadotropin-releasing hormone (GnRH) causes
release of FSH, as well as LH, from the pituitary and
is transported by the blood to their sites of action, the
testes or ovary.
In men, FSH acts on the Sertoli cells of the testis,
stimulating the synthesis of inhibin, which appears to
specifically inhibit further FSH secretion, and
androgen-binding protein. Thus, it indirectly supports
spermatogenesis.
In women, FSH acts on the granulosa cells of the
ovary, stimulatin steroidogensis. All ovulatory
menstrual cycles have a characteristic pattern of FSH,
as well as LH, secretion. The menstrual cycle is
divided into a follicular phase and a luteal phase by
the midcycle surge of the gonadotropins (LH and
FSH). As the follicular phase progresses, FSH
concentration decreases. Near the time ovulation
occur, about midcycle, FSH peaks (lesser in
magnitude than LH) to its highest level.
The clinical usefulness of the measurement of Follicle
Stimulating hormone (FSH) in ascertaining the
homeostasis of fertility regulation via the hypothalamic
- pituitary - gonadal axis has been well established
(1,2).