The Pituitary Gland: Small But Mighty

The pituitary gland works hard to keep you healthy, doing everything from ensuring proper bone and muscle growth to helping nursing mothers produce milk for their babies. Its functionality is even more remarkable when you consider the gland is the size of a pea.

“The pituitary is commonly referred to as the ‘master’ gland because it does so many important jobs in the body,” says Karen Frankwich, MD, a board-certified endocrinologist at Mission Hospital. “Not only does the pituitary make its own hormones, but it also triggers hormone production in other glands. The pituitary is aided in its job by the hypothalamus. This part of the brain is situated above the pituitary, and sends messages to the gland on when to release or stimulate production of necessary hormones.”

These hormones include:

  • Growth hormone, for healthy bone and muscle mass
  • Thyroid-stimulating hormone, which signals the thyroid to produce its hormones that govern metabolism and the body’s nervous system, among others
  • Follicle-stimulating and luteinizing hormones for healthy reproductive systems (including ovarian egg development in women and sperm formation in men, as well as estrogen and testosterone production)
  • Prolactin, for breast milk production in nursing mothers
  • Adrenocorticotropin (ACTH), which prompts the adrenal glands to produce the stress hormone cortisol. The proper amount of cortisol helps the body adapt to stressful situations by affecting the immune and nervous systems, blood sugar levels, blood pressure and metabolism.
  • Antidiuretic (ADH), which helps the kidneys control urine levels
  • Oxytocin, which can stimulate labor in pregnant women

The work of the pituitary gland can be affected by non-cancerous tumors called adenomas. “These tumors can affect hormone production, so you have too little or too much of a certain hormone,” Dr. Frankwich says. “Larger tumors that are more than 1 centimeter, called macroadenomas, can also put pressure on the area surrounding the gland, which can lead to vision problems and headaches. Because symptoms can vary depending on the hormone that is affected by a tumor, or sometimes there are no symptoms, adenomas can be difficult to pinpoint. General symptoms can include nausea, weight loss or gain, sluggishness or weakness, and changes in menstruation for women and sex drive for men.”

If there’s a suspected tumor, a doctor will usually run tests on a patient’s blood and urine, and possibly order a brain-imaging scan. An endocrinologist can help guide a patient on the best course of treatment, which could consist of surgery, medication, radiation therapy or careful monitoring of the tumor if it hasn’t caused major disruption.

“The pituitary gland is integral to a healthy, well-functioning body in so many ways,” Dr. Frankwich says. “It may not be a major organ you think about much, but it’s important to know how it works, and how it touches on so many aspects of your health.”

Learn more about Mission Hospital. Learn more about Dr. Frankwich.

From http://www.stjhs.org/HealthCalling/2016/December/The-Pituitary-Gland-Small-but-Mighty.aspx

Low Oxytocin Levels Linked to Reduced Empathy

People suffering from low levels of oxytocin perform worse on empathy tasks, according to new research presented at the 2016 Society for Endocrinology annual conference.

The research suggests that hormone replacement could improve the psychological well-being of those living with low levels, according to researchers at the University of Cardiff.

Oxytocin is often referred to as the “love hormone” due to its role in human behavior, including sexual arousal, recognition, trust, anxiety, and mother-infant bonding. It is produced by the hypothalamus — an area of the brain that controls mood and appetite — and stored in the pituitary gland.

For the study, researchers investigated empathic behavior in people who they suspected of having reduced oxytocin levels due to one of two medical conditions caused in response to pituitary surgery.

The study assessed 20 people with cranial diabetes insipidus (CDI). In CDI, the body has reduced levels of ADH, a chemical also produced in the hypothalamus and structurally very similar to oxytocin.

The researchers also assessed 15 people with hypopituitarism (HP), a condition in which the pituitary gland does not release enough hormones.

These two patient groups were compared to a group of 20 healthy people.

The researchers gave all participants two tasks designed to test empathy, both relating to the recognition of emotional expression. They also measured each group’s oxytocin levels and found that the 35 CDI and HP participants had slightly lower oxytocin compared to the healthy people. The researchers noted that a larger sample is required to establish statistical significance.

The researchers also discovered that the CDI and HP groups performed significantly worse on empathy tasks, compared to the healthy control group. In particular, CDI participants’ ability to identify expressions was predicted by their oxytocin levels — those with the lowest levels of oxytocin produced the worst performances, according to the study’s findings.

“This is the first study which looks at low oxytocin as a result of medical, as opposed to psychological, disorders,” said Katie Daughters, lead researcher. “If replicated, the results from our patient groups suggest it is also important to consider medical conditions carrying a risk of low oxytocin levels.”

“Patients who have undergone pituitary surgery, and in particular those who have acquired CDI as a consequence, may present with lower oxytocin levels,” she continued. “This could impact on their emotional behavior, and in turn affect their psychological well-being. Perhaps we should be considering the introduction of oxytocin level checks in these cases.”

The researchers said they hope to expand their study to further replicate and confirm their findings. They added that the study presents only preliminary results, and has not been peer reviewed.

Source: Society for Endocrinology

From http://psychcentral.com/news/2016/11/06/low-oxytocin-levels-linked-to-reduced-empathy/112110.html

Hypopituitarism – Deficiency in Pituitary Hormone Production

By Yolanda Smith, BPharm

Hypopituitarism is a health condition in which there is a reduction in the production of hormones by the pituitary gland.

The pituitary gland is located at the base of the brain and is responsible for the production of several hormones, including:

  • Adrenocorticotropic hormone (ACTH), which controls the production of the vital stress hormones cortisol and dehydroepiandrosterone (DHEA) in the adrenal gland
  • Thyroid stimulating hormone (TSH), which controls the production of hormones by the thyroid gland
  • Luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which control the secretion of the primary sex hormones and affect fertility
  • Growth hormone (GH), which regulates the growth processes in childhood and other metabolic processes throughout life
  • Prolactin (PRL), which facilitates the production of breast milk
  • Oxytocin, which is crucial during labor, childbirth and lactation
  • Antidiuretic hormone (ADH), also known as vasopressin, which regulates the retention of water and the blood pressure

An individual with hypopituitarism shows a deficiency in one or more of these hormones. This inevitably leads to abnormal body function, as an effect of the low levels of the hormone in the body, and may result in symptoms.

Causes

Hypopituitarism is most commonly due to the destruction, compression or inflammation of pituitary tissue by a brain tumor in that region. Other causes include:

  • Head injury
  • Infections such as tuberculosis
  • Ischemic or infarct injury
  • Radiation injury
  • Congenital and genetic causes
  • Infiltrative diseases such as sarcoidosis

Symptoms

General symptoms that are associated with pituitary hormone deficiency include:

  • Weakness and fatigue
  • Decreased appetite
  • Weight loss
  • Sensitivity to cold
  • Swollen facial features or body

There are also likely to be more specific symptoms according to the type of pituitary hormone deficiency, such as:

  • ACTH deficiency:
    • abdominal pain
    • low blood pressure
    • low serum sodium levels
    • skin pallor
  • TSH deficiency:
    • generalized body puffiness
    • sensitivity to cold
    • constipation
    • impaired memory and concentration
    • dry skin
    • anemia
  • LH and FSH deficiency:
    • reduction in libido
    • erectile dysfunction in men
    • abnormal menstrual periods
    • vaginal dryness in women
    • difficulty in conceiving
    • infertility.
  • GH deficiency:
    • slow growth
    • short height
    • an increase in body fat

Treatment

The first step in the treatment of hypopituitarism is to identify the cause of the condition.

Secondly, the hormones that are deficient must be identified. From this point, the appropriate treatment decisions can be made to promote optimal patient outcomes.

Hormone replacement therapy is the most common type of treatment for a patient with hypopituitarism.

This may involve supplementation of one or more hormones that are deficient, to reduce or correct the impact of the deficiency.

Follow Up

As hormone replacement therapy is expected to continue on a lifelong basis, it is important that patients have a good understanding of the therapy.

It is especially important to educate patients on what to do in case of particular circumstances that may change their hormone requirements.

For example, during periods of high stress, the demand for many hormones is increased, and the dose of hormone replacement may need to be adjusted accordingly.

It is recommended that patients have regular blood tests to monitor their hormone levels and ensure that they are in the normal range.

Patients should also carry medical identification, such as a medical bracelet or necklace, to show that they are affected by hypopituitarism and inform others about their hormone replacement needs and current treatment. This can help to meet their medical needs in case of any emergency.

Epidemiology

Hypopituitarism is a rare disorder that affects less than 200,000 individuals in the United States, with an incidence of 4.2 cases per 100,000 people per year.

The incidence is expected to be higher in certain subsets of the population, such as those that have suffered from a brain injury. Statistics in reference to these population groups have not yet been determined.

Reviewed by Dr Liji Thomas, MD.

References

From http://www.news-medical.net/health/Hypopituitarism-Deficiency-in-Pituitary-Hormone-Production.aspx