DHT-optimized
The DHT-optimized ELISA is an enzyme immunoassay for the quantitative in vitro diagnostic measurement of total 5α-Dihydrotestosterone (DHT) in human serum or plasma (heparin- or citrate plasma).
DHTis a potent androgenic sex hormone, synthesized from testosteroneby two 5α-reductase isoenzymes mainly in the Leydig cells of the testes, but also in the adrenal gland, prostate and to a lower extend in the ovaries(1).Together with testosterone, androstenedione and dihydroepiandrostenedione (DHEA), DHT belongs to the androgen family of steroid hormones that act by binding to intracellular androgen receptors (AR)(2).DHT and Testosterone bind with similar high affinity to AR, but DHT is the more potent androgen because of more efficient AR cofactor stimulation (3). AR activation regulates prostate growth, bone and muscle mass, and spermatogenesis .Androgens circulate in the blood bound to proteins, especially sex hormone binding globulin (SHBG) and albumin, but trace amounts of these steroids circulate in the unbound form and are referred to as the free hormone fractions (4). The major organ to neutralize androgens is the liver, and the androgen glucuronides are eliminated by renal excretion (5).During embryogenesis, DHT plays an essential role in the formation of the male external genitalia, while in adults DHT acts as the primary androgen in the prostate and in hair follicles.It is responsible for the male secondary sexual characteristics such as deepening of the vocal chords, male hair patterns and male sexual drive and function. DHT levels are high in adolescent men and slowly decrease with aging. DHT levels are very low in females and do not change during the menstrual cycle, but decrease in the postmenopausal phase (6).
The DRG DHT-optimized ELISA Kit is a solid phase enzyme-linked immunosorbent assay (ELISA), based on the principle of competitive binding. The microtiter wells are coated with a polyclonal antibody directed towards an antigenic site of the DHT molecule. Endogenous DHT of a patient sample competes with a DHT-horseradish peroxidase conjugate for binding to the coated antibody. After incubation the unbound conjugate is washed off. The amount of bound peroxidase conjugate is inversely proportional to the concentration of DHT in the sample. After addition of the substrate solution, the intensity of colour developed is inversely proportional to the concentration of DHT in the patient sample.
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