The pineal body, also called the pineal gland, is located in the middle of the brain. It secretes melatonin, a hormone that may help regulate the wake-sleep cycle.
The gonads are the main source of sex hormones. In males, they are located in the scrotum. Male gonads, or testes, secrete hormones called androgens, the most important of which is testosterone. These hormones regulate body changes associated with sexual development, including enlargement of the penis, the growth spurt that occurs during puberty, and the appearance of other male secondary sex characteristics such as deepening of the voice, growth of facial and pubic hair, and the increase in muscle growth and strength. Working with hormones from the pituitary gland, testosterone also supports the production of sperm by the testes.
The female gonads, the ovaries, are located in the pelvis. They produce eggs and secrete the female hormones estrogen and progesterone. Estrogen is involved in the development of female sexual features such as breast growth, the accumulation of body fat around the hips and thighs, and the growth spurt that occurs during puberty. Both estrogen and progesterone are also involved in pregnancy and the regulation of the menstrual cycle.
Pineal body (epiphysis)
Secreted hormone | From cells | Effect |
---|---|---|
Melatonin | Pinealocytes | Antioxidant Monitors the circadian rhythm including inducement of drowsiness and lowering of the core body temperature |
Testes
Secreted hormone | From cells | Effect |
---|---|---|
Androgens (chiefly testosterone) | Leydig cells | Anabolic: growth of muscle mass and strength, increased bone density, growth and strength,Virilizing: maturation of sex organs, formation of scrotum, deepening of voice, growth of beard and axillary hair. |
Estradiol | Sertoli cells | Prevent apoptosis of germ cells[5] |
Inhibin | Sertoli cells | Inhibit production of FSH |
Ovary
Secreted hormone | From cells | Effect |
---|---|---|
Progesterone | Granulosa cells, theca cells | Support pregnancy:[6]
Other:
Anti-inflammatory
|
Androstenedione | Theca cells | Substrate for estrogen |
Estrogens (mainly estradiol) | Granulosa cells | Structural:
Protein synthesis:
Coagulation:
Fluid balance:
Gastrointestinal tract:
Melanin:
Cancer:
Lung function:
|
Inhibin | Granulosa cells | Inhibit production of FSH from anterior pituitary |
Placenta (when pregnant)
Secreted hormone | Abbreviation | From cells | Effect |
---|---|---|---|
Progesterone (Primarily) | Support pregnancy:[6]
Other effects on mother similar to ovarian follicle-progesterone |
||
Estrogens (mainly Estriol) (Also Primarily) | Effects on mother similar to ovarian follicle estrogen | ||
Human chorionic gonadotropin | HCG | Syncytiotrophoblast | Promote maintenance of corpus luteum during beginning of pregnancyInhibit immune response, towards the human embryo. |
Human placental lactogen | HPL | Syncytiotrophoblast | Increase production of insulin and IGF-1Increase insulin resistance and carbohydrate intolerance |
Inhibin | Fetal Trophoblasts | Suppress FSH |
Uterus (when pregnant)
Secreted hormone | Abbreviation | From cells | Effect |
---|---|---|---|
Prolactin | PRL | Decidual cells | milk production in mammary glands |
Relaxin | Decidual cells | Unclear in humans and animals |