Pituitary gland is a tiny pea sized gland located in the brain. It is a master gland which controls number of other endocrine glands present in the body. It is an important gland secreting various hormones which regulate metabolism, blood pressure, growth and various other activities. Pituitary gland is connected to hypothalamus, a part of brain which lies behind it. Hypothalamus sends message to the gland to increase or decrease secretion of hormones whenever necessary.
Pituitary gland is divided into anterior and posterior parts. Anterior portion of the gland is the most active.Together these lobes secrete steroid hormones, growth hormones and thyroid stimulating hormone. Over activity of pituitary gland causes increased secretion of some of these hormones leading to various diseases and disorders.
Causes Of Overactive Pituitary Gland
A small growth, a benign tumor is the major cause of overactive pituitary gland. The exact cause why tumor develops in the pituitary gland is not known. Pituitary gland is made up of five different types of cells. Each cell is known to produce different type of hormone.
For example somatotroph cells produce growth hormone, thyrotrophs cell produces thyroid hormones, gonadotrophs cells produce follicle stimulating hormone (FSH) and luteinizing hormone (LH).
Particular hormone secretion will be increased depending on the cell that is affected. Sometimes over activity may occur due to an inherited condition of pituitary gland called MEN1.
What Are The Symptoms Of An Overactive Pituitary Gland?
Number of diseases can occur due to overactive pituitary gland. The symptoms will depend on the type of disorder and increased secretion of a particular hormone. In medical parlance, overactive pituitary gland is also referred as hyperpituitarism. The disorders and its symptoms are as follows:
- Prolactinoma: It is one of the most common disorders of pituitary gland overactivity. It is a type of pituitary adenoma which secretes prolactin hormone in excess. The disease can affect both men as well as women, but women are more frequently affected. Too much of prolactin hormone can disrupt normal function of ovaries and testes. Prolactin primarily is involved in production of milk and growth of breast tissue. In women this condition can lead to production of milk from breast even if she is not pregnant. It also causes breast tenderness. The other symptoms are stoppage of menses, infertility, and dryness of private parts and loss of energy. Rarely in men there may be secretion of milk from breast.
- Acromegaly: It is a condition caused due to excess secretion of growth hormone. The symptoms of this condition are abnormal tall stature, abnormally long hands and feet, bulbous and long nose, thick lips and tongue, prominent jaw and brow. The skin becomes thick and creases of palm become prominent. Women may suffer from irregular periods. Some patients suffering from acromegaly may have increased risk of high blood pressure and diabetes.
- Cushing syndrome: This condition is characterized by abnormal rise in cortisol hormone level. Cortisol hormone takes part in metabolism of protein, fats and carbohydrates. Symptoms of cushing syndrome is assimilation of fat in the trunk area, excessive hair growth in women on face and above the upper lip, stretch marks on abdomen, easy bruising. Due to increase secretion of steroid hormone cortisol, too much of calcium is lost from the bones. This may cause weak and fragile bones. Many patients suffer from pathological fractures.
Treatment For Overactive Pituitary Gland
Treatment of over active pituitary gland depends on the underlying cause. If tumor is the cause it needs to be surgically removed. In some cases the entire tumor is impossible to be removed due to a risk of damaging the delicate surrounding structures in the brain. In such situation, radiation and chemotherapy may be used after removal of part of the tumor. In most cases transphenoidal surgery is effective if the tumor is small.
In some cases medicines are used to reduce prolactin level for example if the underlying cause is prolactinoma. Hormone therapy is also used to shrink tumors.