Testosterone is a steroid sex hormone found in both men and women. In men, testosterone is produced primarily by the Leydig (interstitial) cells of the testes when stimulated by luteinizing hormone (LH). It functions to stimulate spermatogenesis, promote physical and functional maturation of spermatozoa, maintain accessory organs of the male reproductive tract, support development of secondary sexual characteristics, stimulate growth and metabolism throughout the body and influence brain development by stimulating sexual behaviors and sexual drive. In women, testosterone is produced by the ovaries (25%), adrenals (25%) and via peripheral conversion from androstenedione (50%). Testerone in women functions to maintain libido and general wellbeing. Testosterone exerts a negative feedback mechanism on pituitary release of LH and follicle-stimulating hormone (FSH). Testosterone may be further converted to dihydrotestosterone or estradiol depending on the tissue.
Synonyms
17beta-hydroxy-4-androsten-3-one
17beta-Hydroxy-4-androsten-3-one
4-Androsten-17beta-ol-3-one
4-androsten-17β-ol-3-one
Androderm
Depo-Testadiol
Mertestate
Synandrol F
Testosteron
Testosterona
Testostérone
Testosteronum
Testoxyl
Testryl
Virosterone
Salts
Testosterone Cypionate
Testosterone Enanthate
Testosterone Heptanoate
Testosterone Propionate
Testosterone Undecanoate
Brand Names
Andriol
Androderm
Androgel
Aveed
Axiron
Delatestryl
Depo-testosterone
Depo-testosterone Inj 100mg/ml
Affected Organism
Humans and other mammals
Indication
To be used as hormone replacement or substitution of diminished or absent endogenous testosterone. Use in males: For management of congenital or acquired hypogonadism, hypogonadism associated with HIV infection, and male climacteric (andopause). Use in females: For palliative treatment of androgen-responsive, advanced, inoperable, metastatis (skeletal) carcinoma of the breast in women who are 1-5 years postmenopausal; testosterone esters may be used in combination with estrogens in the management of moderate to severe vasomotor symptoms associated with menopause in women who do not respond to adequately to estrogen therapy alone.
Pharmacology
Testosterone is a steroid hormone from the androgen group. Testosterone is primarily secreted from the testes of males. In females, it is produced in the ovaries, adrenal glands and by conversion of adrostenedione in the periphery. It is the principal male sex hormone and an anabolic steroid. In both males and females, it plays key roles in health and well-being. Examples include enhanced libido, energy, immune function, and protection against osteoporosis. On average, the adult male body produces about twenty times the amount of testosterone than an adult female's body does.
Mechanism of action
The effects of testosterone in humans and other vertebrates occur by way of two main mechanisms: by activation of the androgen receptor (directly or as DHT), and by conversion to estradiol and activation of certain estrogen receptors. Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5α-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5α-reductase. DHT binds to the same androgen receptor even more strongly than T, so that its androgenic potency is about 2.5 times that of T. The T-receptor or DHT-receptor complex undergoes a structural change that allows it to move into the cell nucleus and bind directly to specific nucleotide sequences of the chromosomal DNA. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects.
Route of administration
Buccal
Intramuscular
Nasal
Oral
Subcutaneous
Topical
Transdermal
Categories
3-Oxoandrosten (4) Derivatives
Anabolic Agents
Androgens
Androstanes
Androstenes
Androstenols
BCRP/ABCG2 Substrates
Chemical Actions and Uses
Combined Inhibitors of CYP3A4 and P-glycoprotein
Cytochrome P-450 CYP2B6 Inducers
Cytochrome P-450 CYP2B6 Substrates
Cytochrome P-450 CYP2C19 Substrates
Cytochrome P-450 CYP2C8 Substrates
Cytochrome P-450 CYP2C9 Substrates
Cytochrome P-450 CYP3A Inducers
Cytochrome P-450 CYP3A Inhibitors
Cytochrome P-450 CYP3A4 Substrates
Delayed-Action Preparations
Genito Urinary System and Sex Hormones
Gonadal Hormones
Gonadal Steroid Hormones
Hormones
Hormones, Hormone Substitutes, and Hormone Antagonists
Drug Info/Drug Targets: DrugBank 3.0: a comprehensive resource for 'omics' research on drugs. Knox C, Law V, Jewison
T, Liu P, Ly S, Frolkis A, Pon A, Banco K, Mak C, Neveu V, Djoumbou Y, Eisner R, Guo AC, Wishart DS.
Nucleic Acids Res. 2011 Jan; 39 (Database issue):D1035-41. | PMID:21059682
