Estrogens, Progesterone, and Sex Hormones

What are the main sources of testosterone and estrogens?

Testosterone: Interstitial (Leydig) cells in testes
Estrogens: Ovarian follicle cells
Progesterone: Corpus luteum

What are the main actions of androgens in males?

Development of male sexual organs
Secondary sexual characteristics
Anabolic effects: Protein synthesis, muscle and bone growth

What are the effects of ovarian hormones?

Regulate menstrual cycle, fertilization, pregnancy, birth, and lactation

What are the two types of estrogen receptors and where are they found?

• ERα: Uterus, mammary glands, bone, CV system

• ERβ: Lungs, GIT, prostate, urinary tract

When is progesterone mainly secreted, and by what structure?

• Secreted in the second half of the menstrual cycle

• Produced by the corpus luteum

What are the main functions of progesterone?

• Prepares endometrium for implantation

• Stimulates mammary gland development in pregnancy

• Thermogenic effect

• Supports bone health (via osteoblast receptors)

What is the clinical implication of low progesterone post-menopause?

May contribute to postmenopausal osteoporosis