| 单词 | testosterone | |||
| 释义 | testosteroneenUKtes·tos·ter·oneT0127500 (tĕs-tŏs′tə-rōn′)testosterone(tɛˈstɒstəˌrəʊn)tes•tos•ter•one(tɛsˈtɒs təˌroʊn)n. tes·tos·ter·one(tĕs-tŏs′tə-rōn′)testosterone
testosteroneenUKtestosterone(tĕstŏs`tərōn), principal androgen, or male sex hormonehormone,secretory substance carried from one gland or organ of the body via the bloodstream to more or less specific tissues, where it exerts some influence upon the metabolism of the target tissue. ..... Click the link for more information. . One of the group of compounds known as anabolic steroidssteroids, class of lipids having a particular molecular ring structure called the cyclopentanoperhydro-phenanthrene ring system. Steroids differ from one another in the structure of various side chains and additional rings. Steroids are common in both plants and animals. ..... Click the link for more information. , testosterone is secreted by the testes (see testistestis or testicle , one of a pair of glands that produce the male reproductive cells, or sperm. In fetal life the testes develop in the abdomen, then descend into an external sac, the scrotum. ..... Click the link for more information. ) but is also synthesized in small quantities in the ovariesovary, ductless gland of the female in which the ova (female reproductive cells) are produced. In vertebrate animals the ovary also secretes the sex hormones estrogen and progesterone, which control the development of the sexual organs and the secondary sexual characteristics. ..... Click the link for more information. , cortices of the adrenal glandsadrenal gland or suprarenal gland , endocrine gland (see endocrine system) about 2 in. (5.1 cm) long situated atop each kidney. The outer yellowish layer (cortex) of the adrenal gland secretes about 30 steroid hormones, the most important of which are aldosterone and ..... Click the link for more information. , and placenta, usually from cholesterolcholesterol , fatty lipid found in the body tissues and blood plasma of vertebrates; it is only sparingly soluble in water, but much more soluble in some organic solvents. A steroid, cholesterol can be found in large concentrations in the brain, spinal cord, and liver. ..... Click the link for more information. . Testosterone is necessary in the fetus for the development of male external genitalia; increased levels of testosterone at puberty are responsible for further growth of male genitalia and for the development and maintenance of male secondary sex characteristics such as facial hair and voice changes. Testosterone also stimulates protein synthesis and accounts for the greater muscular development of the male (see metabolismmetabolism, sum of all biochemical processes involved in life. Two subcategories of metabolism are anabolism, the building up of complex organic molecules from simpler precursors, and catabolism, the breakdown of complex substances into simpler molecules, often accompanied by ..... Click the link for more information. ). An abnormally low testosterone level in men, known as hypogonadism, is treated with testosterone, but it is not clear if testosterone is a safe or effective treatment for so-called low testosterone, such as the lower levels of testosterone typically found in older men. In men with lower testosterone, the level can often be raised by increasing exercise, improving diet, and reducing weight to the recommended range. For many years, synthetic steroids similar to testosterone have been used by athletes with the goal of improving performance, but medical research has shown that these drugs may have a wide range of harmful side effects and their use is now typically banned (see anabolic steroidanabolic steroid Testosterone(also 17 β-hydroxyandrost-4-en-3-one), the principal male sex hormone; chemically, a steroid. Testosterone occurs as colorless crystals having a melting point of 155°C. It is sparingly soluble in water but soluble in organic solvents. (The substance was first obtained in 1935. Here, testosterone in crystalline form was isolated from bovine testis tissue, 100 kg of tissue yielding 10 mg of hormone.) In humans and other higher vertebrates, testosterone is produced by the sex glands, mainly the testes, as well as by the adrenal glands, placenta, and liver. Intermediate products in the biosynthesis of testosterone include cholesterol and progesterone.
The normal level of testosterone in the blood of a man is 0.5–0.6 microgram per 100 milliliters; in a woman, the level is 0.12 microgram per 100 milliliters. A man produces approximately 15 mg of testosterone per day. Testosterone promotes the development of male sexual organs and of secondary sex characteristics. It affects the differentiation of sexual organs and bodily structures of vertebrates developing in the uterus. The concentration of testosterone in the blood probably serves as the factor determining masculinization in males and virilism in females. Other androgens are active only after their conversion into testosterone. Testosterone is used in medicine in substitution therapy when there are insufficiencies in the functioning of sex glands in men. It is also used for climacteric disorders in women and for certain types of tumors. Intake of testosterone over prolonged periods blocks the secretion of gonadotrophic hormones and suppresses sexual activity. In the pharmaceutical industry, the hormone is obtained from sterols and steroid saponins. Highly active synthetic analogues of testosterone, such as testosterone propionate and methyltestosterone, are used in medical practice. REFERENCESFieser, L., and M. Fieser. Steroidy. Moscow, 1964. (Translated from English.)Heftmann, E. Biokhimiia steroidov. Moscow, 1972. (Translated from English.) E. P. SEREBRIAKOV testosterone[tes′täs·tə‚rōn]testosteronetestosteroneenUKtestosterone[tes-tos´tĕ-rōn]Testosterone is obtained for therapeutic purposes by extraction from animal testes or by synthesis from cholesterol in a laboratory. It is used to treat male hypogonadism and delayed male puberty as well as to relieve symptoms in some forms of metastatic breast cancer in females, and is used as the base for various esters (e.g., cypionate, enanthate, propionate). Women normally secrete a certain amount of male hormones; however, if the hormone balance is disturbed and there is overproduction of male hormones in a woman, masculinization may develop. testosteronetestosterone cypionatetestosterone enanthatePharmacologic class: Hormone Therapeutic class: Androgenic and anabolic steroid, antineoplastic Controlled substance schedule III Pregnancy risk category X FDA Box WarningVirilization has occurred in children secondarily exposed to testosterone gel. Children should avoid contact with unwashed or unclothed application sites in men using testosterone gel. Health care providers should advise patients to strictly adhere to recommended instructions for use. ActionResponsible for normal growth and development of male sex organs and maintenance and maturation of secondary sex characteristics. Also decreases estrogen activity, which aids treatment of some breast cancers. Availabilitytestosterone Buccal system: 30 mg Gel: 1% (25 mg, 50 mg), 1.62% (metered-dose pump delivers 20.25 mg/actuation), 2% (10 mg/one metered-dose pump actuation) Injection (aqueous suspension): 100 mg/ml Pellets (subcutaneous implant): 75 mg Solution (topical): 30 mg/metered-dose pump actuation Transdermal system: 2 mg/day, 4 mg/day testosterone cypionate Injection: 100 mg/ml, 200 mg/ml testosterone enanthate Injection (in oil): 200 mg/ml Indications and dosages➣ Male hypogonadism Adult males: 10 to 25 mg (testosterone) I.M. two to three times weekly or 50 to 400 mg (enanthate) I.M. q 2 to 4 weeks for 3 to 4 years. Or 150 to 450 mg (pellet) implanted subcutaneously q 3 to 6 months. Or, 4 mg (transdermal system) daily, adjusted to 2 mg or 6 mg based on serum testosterone level. Or, 60 mg (one 30-mg actuation of Axiron topical solution applied to each axilla) daily at same time each morning, adjusted to 30 mg (one pump actuation) or increased from 60 to 90 mg (three pump actuations) or from 90 to 120 mg (four pump actuations) based on serum testosterone concentration from single blood draw 2 to 8 hours after applying solution and at least 14 days after starting treatment or following dosage adjustment. Or, 40 mg (four actuations of Fortesta topical gel) applied to clean, intact skin of thighs once daily in morning, adjusted to 10 mg (one pump actuation) or up to 70 mg (seven pump actuations) based on total serum testosterone level 2 hours after applying gel at approximately 14 days after starting treatment or following dosage adjustment. Or, 50 mg testosterone gel (AndroGel 1%) daily applied topically, adjusted up to 75 mg daily within 14 days, with subsequent dosages up to 100 mg daily. Or, 30 mg (buccal system) to gum region b.i.d. Or, 50 to 400 mg I.M. (cypionate) q 2 to 4 weeks. ➣ Delayed puberty Adult males: 50 to 200 mg I.M. (enanthate only) q 2 to 4 weeks for limited duration (4 to 6 months); or 150 to 450 mg subcutaneously (pellets) q 3 to 6 months ➣ Inoperable breast cancer in women 1 to 5 years after menopause Adults: 200 to 400 mg I.M. (enanthate) q 2 to 4 weeks Contraindications• Hypersensitivity to drug, its components, or tartrazine • Males with breast cancer or suspected prostate cancer • Females (buccal or transdermal systems or gel) • Pregnancy or breastfeeding PrecautionsUse cautiously in: • diabetes mellitus; edema associated with serious cardiac, hepatic, or renal disease; sleep apnea; hypercalcemia • children younger than age 18 (safety and efficacy not established). Administration• Evaluate elderly patients and patients at increased risk for prostate cancer for presence of prostate cancer before starting testosterone replacement therapy. • Inspect aqueous solution for injection. If crystals are visible, warm bottle and shake contents to dissolve crystals. • Rotate I.M. injection sites within upper outer quadrant of gluteus maximus. Inject deeply into muscle. • Apply gel once daily to clean, dry, intact skin on shoulder, upper arm, or abdomen. • Place buccal system just above incisor tooth. Have patient hold it in place for 30 seconds to ensure adhesion. Rotate to other side of mouth with each application.  Adverse reactionsCNS: headache, depression, emotional lability, nervousness, anxiety, asthenia, memory loss, dizziness, vertigo, cerebrovascular accident CV: edema, peripheral edema, deepvein phlebitis, heart failure GI: bleeding GU: hematuria, urinary tract infection, impaired urination, scrotal cellulitis, benign prostatic hyperplasia, scrotal papilloma (with transdermal use), prostatitis, libido changes, breast pain or tenderness, gynecomastia, virilization in females, excessive hormonal effects in males Hematologic: polycythemia, leukopenia, suppressed clotting factors Hepatic: hepatic adenoma (with long-term enanthate use) Metabolic: hyperphosphatemia, hypernatremia, hypercalcemia, hypoglycemia, hyperkalemia Musculoskeletal: myalgia Respiratory: sleep apnea Skin: acne; rash, itching, burning, discomfort, irritation, burn-like blister, erythema (with transdermal use); pain, local edema, and induration at injection site (with I.M. or subcutaneous use) Other: accidental injury, flulike symptoms, hypersensitivity reaction InteractionsDrug-drug. Corticosteroids: increased risk of edema Hepatotoxic drugs: increased risk of hepatotoxicity Insulin, oral hypoglycemics: decreased blood glucose level Oral anticoagulants: increased anticoagulant effect Oxyphenbutazone: increased oxyphenbutazone blood level Propranolol: increased propranolol clearance Drug-diagnostic tests. Bilirubin, liver function tests: abnormal results Calcium, cholesterol, hematocrit, hemoglobin, phosphate, prostate-specific antigen (with topical use), sodium: increased levels Clotting factors, creatine excretion, glucose, serum creatinine, thyroxine, thyroxine-binding globulin: decreased levels Urine creatine and creatinine: decreased excretion Urine 17-ketosteroids: increased excretion Drug-herbs. Chaparral, comfrey, germander, jin bu huan, kava, pennyroyal: increased risk of hepatotoxicity Patient monitoring• Monitor electrolyte levels, liver function tests, blood and urine calcium levels, lipid panels, CBC with white cell differential, and semen studies. • Assess diabetic patient carefully for hypoglycemia. • Closely monitor neurologic status. Stay alert for sleep apnea. • Assess for early signs of excessive hormonal effects in females (virilization). If these occur, drug withdrawal may be indicated. Patient teachingInstruct patient to immediately report signs and symptoms of liver problems, including nausea, vomiting, yellowing of skin or eyes, and ankle swelling. • Teach prepubertal male about signs and symptoms of excessive hormonal effects, such as acne, priapism, increased body and facial hair, and penile enlargement. • Teach postpubertal male about signs and symptoms of excessive adverse hormonal effects, such as erectile dysfunction, gynecomastia, epididymitis, testicular atrophy, and infertility. Tell female patient to immediately report signs of masculinization, such as excessive body or facial hair, deepening of voice, clitoral enlargement, and menstrual irregularities. • Advise female of childbearing age to use barrier contraceptives. Caution her not to breastfeed. • Tell patient which transdermal patches can be applied to scrotum. Instruct him to apply patch daily to clean, dry skin after removing protective liner to expose drug-containing film. To prevent irritation, instruct him to apply each patch to a different site, waiting at least 1 week before reusing same site. • Advise patient to apply topical gel once daily to clean, dry skin on shoulder, upper arm, or abdomen. Tell him that after opening packet, he should squeeze entire contents into palm and apply immediately. Instruct him to wait until gel dries before getting dressed. • Teach patient to place buccal system in comfortable position just above incisor tooth and hold it in place for about 30 seconds to ensure adhesion. Tell him to use opposite side of mouth with each application. Caution him not to dislodge buccal system, especially when eating, drinking, brushing teeth, or using mouthwash. If system doesn't properly adhere or falls out during 12hour dosing interval, tell him to discard it and apply new system. If it falls out within 4 hours of next dose, tell him to apply new system and keep it in place until next regularly scheduled dose. • Instruct patient to apply topical solution to clean, dry, intact skin of axilla area only and to allow application site to dry completely before dressing. Advise patient to wash axilla with soap and water to remove any testosterone residue if direct skin-to-skin contact with another person is anticipated. • Tell patient drug shouldn't be used to enhance athletic performance or physique. • As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and herbs mentioned above. tes·tos·te·rone(tes-tos'tĕ-rōn),testosterone(tĕs-tŏs′tə-rōn′)testosteroneEndocrinology The principal and most potent of the C-19 androgenic steroids, produced from its precursor hormone, progesterone, by the Leydig cells of testis, and, in far lesser amounts, in the ovary and adrenal cortex, and drives the development and maintenance of ♂ sex characteristics Activity Nitrogen retention, buildup of protein, induction and maintenance of 2º ♂ characteristics–eg, facial hair; testosterone secretion is in turn regulated by LH, which is produced by the anterior pituitary Indications Treatment of sexual dysfunction, weight loss, depression Ref range ♂–total, 300–1000 ng/dL; free, 5.1–41.0 ng/dL; ♀–total, 20-90 ng/dL; free, 0.1–2.3 ng/dL ↑ in ♂ sexual precocity, hyperplasia of adrenal cortex, adrenogenital syndrome, polycystic ovary syndrome ↓ in Alcoholism, anterior pituitary gland hypofunction, estrogen therapy, Klinefelter syndrome–aka 1º hypogonadism, testicular hypoactivity. See Sublingual testosterone. Cf Progesterone.tes·tos·ter·one(tes-tos'tĕ-rōn)Compare: bioregulator testosteroneThe principal male sex hormone (androgen) produced in the INTERSTITIAL cells of the TESTIS and, to a lesser extent in the OVARY. Testosterone is ANABOLIC and stimulates bone and muscle growth and the growth of the sexual characteristics. It is also used as a drug to treat delayed puberty or some cases of infertility or to help to treat breast cancer in post-menopausal women. It may be given by mouth, depot injection or skin patch. The drug is on the WHO official list. Brand names are Andropatch, Restandol, Sustanon, Testogel and Virormone.testosteronea steroid ANDROGEN produced by the LEYDIG CELLS between the SEMINIFEROUS TUBULES of the TESTIS. It causes the development and maintenance of accessory sex organs, the genitalia and the SECONDARY SEXUAL CHARACTERS.Testosteronetes·tos·ter·one(tes-tos'tĕ-rōn)testosteroneenUK
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