The endocrine system is a complex network of glands and organs. It uses hormones to
control and coordinate your body's metabolism, energy level, reproduction, growth
and development, and response to injury, stress, and mood. The following are key parts
of the endocrine system:
Hypothalamus. The hypothalamus is located at the base of the brain. It makes hormones that control
hormones released in the pituitary gland. The hypothalamus controls water balance,
sleep, temperature, appetite, mood, reproductive behaviors, and blood pressure.
Pineal gland. This gland is located in the middle of the brain. It makes the hormone melatonin.
This hormone helps your body know when it's time to sleep. This hormone also regulates
the timing of other functions throughout the body, such as when puberty starts.
Pituitary gland. This gland is located below the brain. It is often as small as a pea. But it controls
many functions of the other endocrine glands.
Thyroid and parathyroid. These glands are located in front of the neck, below the voice box (larynx). The thyroid
plays a key role in the body's metabolism. The parathyroid helps regulate the body's
calcium balance and bone strength.
Adrenal gland. An adrenal gland is located on top of each kidney. Like many glands, these work together
with the hypothalamus and pituitary gland. The adrenal glands make and release corticosteroid
hormones and adrenaline (epinephrine). These maintain blood pressure and regulate
Pancreas. This organ is located across the back of the belly (abdomen), behind the stomach.
It plays a role in digestion and hormone production. Hormones made by the pancreas
include insulin and glucagon. These regulate blood sugar levels.
Ovaries. A woman's ovaries are located on both sides of the uterus, below the opening of the
fallopian tubes. The ovaries contain the egg cells needed for reproduction. They also
make estrogen and progesterone.
Testes. A man's testes are located in a pouch that hangs suspended outside the male body.
The testes make testosterone and sperm.