Testosterone
TestosteronTestosteron – chief representative of androgen (male) hormones.It monitors the development of secondary sexual characteristics in men.The most important source of testosterone are Leydig cells of the testes.In much smaller amounts of a hormone produced in the adrenal cortex and ovaries.Testosterone maintains spermatogenesis.stimulates the growth and functioning of the gonads.responsible for puberty.The hormone has an anabolic effect, mainly in relation to bone and muscle.Due to direct effects on bone marrow and activation of synthesis of erythropoietin in the kidney testosterone stimulates erythropoiesis.Hormone needed to maintain libido and potency.
The normal concentration of testosterone in the blood increases after intense exercise.decrease in concentration occurs after ingestion of glucose.
The basic amount of circulating testosterone is associated with testosterone-glycoprotein estradiolsvyazyvayuschim.Biologically active form of the hormone testosterone is free.
In men, there is a diurnal rhythm of testosterone release.The peak discharge accounts for 7-00 hours at least – for 20-00 hours.After 60 years there is a progressive decline in hormone levels.
In women, testosterone levels are on average 10 times lower than men's.Increase in its concentration may interfere with normal menstrual cycle.therefore the determination of testosterone is necessary for identifying the cause of infertility.with signs of hirsutism.Increased levels of testosterone in women with polycystic be syndrome.adrenal / ovarian tumors.
Normal values of testosterone in serum:
Women:
Taking oral contraceptives – 0,13-0,83 ng / ml
Not taking oral contraceptives – 0,09-1,09 ng / ml
Postmenopausal women – 0,12-1,3 ng / ml
Men:
to 50 years – 1,66-8,77 ng / ml
after 50 years – 1,56-5,63 ng / ml
