FSH

The DRG:HYBRiD-XL FSH is an enzyme immunoassay for the quantitative in vitro diagnostic measurement of Follicle-Stimulating Hormone (FSH) in serum and plasma.Only for use with the DRG:HYBRiD-XL Analyzer.Follicle-Stimulating Hormone (FSH) and Luteinizing Hormone (LH) exert their principal function in the gonads, where gametogenesis, folliculogenesis, and steroidogenesis occur (1,2). FSH is a glycoprotein secreted by the basophil cells of the anterior pituitary after pulsatile secretion of Gonadotropin-releasing hormone (GnRH) in the hypothalamus (3).Like other glycoproteins, such as LH, TSH, and HCG, FSH is a heterodimer assembled from of a common -subunit and a unique -subunit (4). Production of GnRH and thegonadotropins is modulated by a negative feedback loop to both the hypothalamus and pituitary by inhibin B as well as estradiol and progesterone in females, and testosterone in males (5). In the female, FSH stimulates the growth and maturation of ovarian follicles by acting directly on the receptors located on the cell surface of granulosa cellsin the ovary, thereby promoting follicular steroidogenesis and stimulating LH production. FSH, LH, and estradiol are therefore intimately related in supporting ovarian recruitment and maturation (5). In women, FSH levels are elevated in ovarian insufficiency (menopause or premature ovarian failure), polycystic ovarian syndrome (PCO) (6),or hyperthyroidism (7). Low FSH levels are observed in hypothalymic dysfunction, dysfunction or tumors of the pituitary gland, and oral contraceptives (8,9). Abnormal relationships between FSH and LH or estrogen have been linked to anorexia nervosa (10). In the male, FSH regulates spermatogenesis by acting on Sertoli cells of seminiferous tubules (10). FSH levels are elevated in primary hypogonadism (e.g.Klinefelter syndrome) (11) and in dysfunction of spermatogenesis. Furthermore, azoospermic and oligospermic males usually have elevated FSH levels (12). High levels of FSH in men can also be found in primary testicular failure. Low to normal serum concentrations of the FSH and LH are found in hypognoadotropic hypogonadism, induced by isolated gonadotropin-releasing hormone (GnRH) deficiency (IGD) (13,14).The DRG:HYBRiD-XL FSH Kit is a solid phase enzyme-linked immunosorbent assay (ELISA) based on the sandwich principle. The antibody coated wells (ACW) of the reagent cartridges are coated with a monoclonal (mouse) antibody directed towards a unique antigenic site of the FSH molecule. An aliquot of patient sample containing endogenous FSH is incubated in the coated well with enzyme conjugate, which is an anti-FSH antibody conjugated with horseradish peroxidase. After incubation the unbound conjugate is washed off. The amount of bound peroxidase conjugate is proportional to the concentration of FSH in the sample. Having added the substrate solution, the intensity of color developed is proportional to the concentration of FSH in the patient sample.