The pituitary gland

The pituitary gland is a small, pea-sized gland found inside the skull and below the brain. As part of the endocrine system, the pituitary gland makes many different hormones that travel throughout the body. These hormones control certain body functions and tell other glands to make other hormones.

The pituitary gland is behind the nasal cavity and lies just above a sinus (sphenoid sinus). The pituitary gland is connected to a part of the brain called the hypothalamus.

The pituitary gland is divided into 2 parts (lobes). The front part closer to the face is called the anterior pituitary gland. The back part is called the posterior pituitary gland, and it is closer to the back of the head. The pituitary gland is surrounded by bone (sphenoid bone), and it sits in a pouch called the sella turcica.

Pituitary gland hormones

The pituitary gland makes 9 different hormones. Both the anterior pituitary gland and the posterior pituitary gland make hormones.

Anterior pituitary gland hormones

The following hormones are made by the anterior pituitary gland:

Adrenocorticotrophic hormone (ACTH) tells the adrenal glands to make cortisol and other steroid hormones. Cortisol has many different jobs, such as controlling blood sugar levels and helping the body respond to stress. ACTH is also called corticotropin.

Growth hormone promotes the growth of all tissues of the body, including bones and muscles. It is needed for normal growth in children. It helps maintain body tissues in adults. Growth hormone is also called somatotropin.

Thyroid-stimulating hormone (TSH) encourages the thyroid to make and release hormones that control growth, body temperature and heart rate and change food into energy. TSH is also called thyrotropin.

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) control the sex organs. In women, FSH and LH tell the ovaries to make the female sex hormones estrogen and progesterone and control the release of eggs (ovulation). In men, FSH and LH get the testicles to make sperm and the male sex hormone testosterone. FSH and LH are called gonadotropins.

Prolactin stimulates breasts to develop and make milk after childbirth. Prolactin is also called lactotropin.

Melanocyte-stimulating hormone (MSH) causes certain cells of the skin (called melanocytes) to make melanin, which is the substance that gives skin its colour and helps protect the body from some of the harmful effects of the sun.

Posterior pituitary gland hormones

The following hormones are made by the posterior pituitary gland:

Antidiuretic hormone (ADH) keeps water in the body so that it’s not all lost. It lowers the amount of urine the kidneys make and helps control blood pressure. ADH is also called vasopressin.

Oxytocin instructs the uterus to contract during labour and childbirth and the breasts to release milk after childbirth. In men, oxytocin causes the prostate to contract.

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