The pituitary gland is an important part of the endocrine system, ultimately governing all of the hormones in the body. But what exactly is it, what does it do, and where is it found?
The pituitary gland is known as the master gland of the endocrine system as it controls all of the other endocrine glands, stimulating them to produce their own hormones. It is found at the base of the brain just behind the nose and it is attached to the hypothalamus by nerve fibres. It is no larger than a pea. The pituitary gland is made up of three lobes – the anterior lobe, the intermediate lobe, and the posterior lobe. Each lobe is responsible for the production of certain hormones.
The pituitary gland is responsible for producing and controlling hormones. Each lobe of the gland has a different function:
The anterior lobe produces the following:
• growth hormone – this is concerned with regulating a person’s height, contributes to bone and muscle building, and also restricts the accumulation of body fat
• prolactin – this stimulates milk production after giving birth
• ACTH (adrenocorticotropic hormone) – this stimulates the adrenal glands to produce cortisol, which is essential to the body and also helps to regulate blood pressure and blood sugar levels
• TSH (thyroid stimulating hormone) – stimulates the thyroid gland to produce thyroxine, which regulates energy expenditure in the body
• FSH (follicle stimulating hormone) – stimulates the ovaries and testes, regulating the menstrual cycle, sperm production, and sex hormone levels in males and females
• LH (luteinising hormone) – stimulates the ovaries or testes, regulating the menstrual cycle, sperm production, and sex hormone levels in males and females
The intermediate lobe produces the following:
• melanocyte stimulating hormone – this hormone controls pigmentation of the skin
The posterior lobe produces the following:
• ADH (antidiuretic hormone) – this is responsible for increasing the absorption of water into the blood by the kidneys and helps the kidneys to maintain the correct water balance in the body
• oxytocin – stimulates milk production and contracts the uterus during childbirth; it is also thought to help counteract the physical effects of stress