Table of Contents
It has many functions and it is responsible for normal growth, development of the male sex organs and maintenance of the secondary sex characteristics.
Testosterone is also important for maintaining
- muscle bulk,
- adequate levels of red blood cells,
- bone growth,
- sense of well-being and
- Sexual function.
The production and secretion of testosterone is highly controlled by some other glands in the body and their hormones. The main controllers are definitely the hypothalamus and the pituitary gland. Hypothalamus is secreting Gonadotropin-releasing hormone (GnRH) which controls the secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) produced by the pituitary gland.
- Luteinizing hormone regulates the production and secretion of testosterone by the Leydig cells of the testes, and
- FSH stimulates spermatogenesis.
Another important fact is that females have a low level of testosterone. It is being produced by the theca cells of the ovaries, by the placenta, as well as by the adrenal cortex, in both sexes.
Testosterone effects on human
- Genital virilization
- Development of prostate and seminal vesicles
Early postnatal effects:
- Adult-type body odor
- Increased oiliness of skin and hair, acne
- Axillary hair
- Accelerated bone maturation
Advanced postnatal effects:
- Increased libido and erection frequency
- Pubic hair extends toward umbilicus
- Facial hair
- Chest hair
- Subcutaneous fat in face decreases
- Increased muscle strength and mass
- Deepening of the voice
- Growth of the Adam’s apple
- Growth of spermatogenesis tissue in testes, male fertility
- Shoulders widen and rib cage expands
- Completion of bone maturation and termination of growth.