[Biology Class Notes] on Pituitary Gland Pdf for Exam

The pituitary gland is a brain-based endocrine gland. It creates hormone-like substances which are chemical messengers that help organs communicate.

The endocrine system includes the pituitary gland. By releasing hormones into your bloodstream, the pituitary gland aids in the control of your body’s processes. These hormones go through your bloodstream to their intended destination.

They usually cause the release of the second hormone in this situation. The target can be specialised endocrine glands or other types of body tissue, such as cell groups.

Because it regulates several other hormone-releasing glands, the pituitary gland is sometimes referred to as the master gland. The pituitary gland regulates several glands, including the thyroid, ovaries, testicles (testes), and adrenal glands.

Pituitary Gland – Function and Disorders

Function

The thyroid gland, adrenal gland, ovaries, and testicles are all controlled by the master gland. While it controls these glands, it receives orders from its neighbour, the hypothalamus.

The pituitary gland produces hormones that tell the glands how much hormone they should produce.

The pituitary gland also manufactures hormones for the body’s organs like:

• Oxytocin stimulates contractions in the uterus and mammary glands, which in turn aid in childbirth and milk production.

• Vasopressin is an antidiuretic hormone that helps the kidneys function properly.

• A beta-melanocyte-stimulating hormone is a hormone that causes the skin to darken.

• Endorphins are neurotransmitters that help the brain and immune system reduce pain and control the immune system.

• Hormones that promote muscle and bone growth.

• Enkephalins are pain-blocking brain chemicals.

Most hormones are released every one to three hours, following the body’s circadian rhythm. Hormone production peaks throughout the day and declines at night. 

Disorders

Pituitary disorders are caused by the pituitary gland being either excessively active or inactive. An isolated portion of the pituitary gland, known as a pituitary adenoma, frequently causes complications (if it is large it may be called pituitary macroadenoma). 

These tumours are normally benign and non-cancerous. Adenomas of the pituitary gland can create issues by:

• Excess of one or more hormones is released.

• Not producing hormones but pressing on normal pituitary tissue, causing the normal function to be disrupted; and/or

• Putting pressure on surrounding structures, such as the eye’s nerve, results in blurred vision or the loss of a portion of eyesight.

The pituitary gland produces too much of one or more of its hormones in the following conditions:

• Acromegaly

• Cushing’s syndrome

• Prolactinoma

The pituitary gland produces insufficient hormones in the following conditions:

• When adult growth hormones are deficient.

• Diabetes insipidus which is a kind of diabetes that affects the kidneys.

• Hypopituitarism.

• Tumours of the pituitary gland.

• Hypothalamic tumours or injuries that have a knock-on impact on the pituitary gland.