Depression has been linked to disruptions in the body’s stress center — the hypothalamic pituitary adrenal (HPA) axis. The HPA is a complex communication system between the hypothalmus, the pituitary gland and the adrenal glands.
The hypothalamus is a region of the brain that controls an immense number of bodily functions including but not limited to emotions, behavior, pain and pleasure.
The pituitary gland is again divided into two distinct portions: the anterior (front) pituitary and the posterior (back) pituitary portions. For the sake of this article, I will only discuss the significance of the anterior pituitary and it’s relation to depression.
The anterior pituitary produces six very important hormones. Each has a different and distinct function necessary for maintaining health and well-being. One hormone of special interest for the topic of depression is called Adrenocorticotropin.
Now with some basic physiology under your belt, here is what happens to a person suffering with depression.
First, when a person experiences some powerful depressing thought, the hypothalamus is sent a signal to wake the pituitary up telling it to produce some of its hormones. The hypothalmus is basically a collecting center for information concerned with the well-being of the body, and in turn much of this information is used to stimulate the pituitary to produce it’s hormones.
The one hormone just discussed is called Adrenocorticotropin. This in turn sends a signal to the adrenal glands to produce more and more of its hormones. Adrenal gland secretion of the hormones cortisol and DHEA has been directly tied to stress and other emotional factors.
A strong relationship between the overproduction of cortisol and mood variations has been established in both depressed and healthy individuals. As with many of the body’s physiological responses, balance is the key. Overactivity of the body’s stress system is associated with anxiety, insomnia, loss of libido, while underactivity is linked to depression with accompanying fatigue, lethargy, indifference.
Depressed individuals often exhibit trouble in the normal relationship between the hypothalmic, pituitary and adrenal glands. A hyperactive Hypothalamic-Pituitary-Adrenal axis, may likely result in a hypersecretion (too much) of cortisol which in turn will also result in depressive symptoms.
It is important to know how your hypothalmic pituitary adrenal (HPA) axis is functioning. With that information in hand, your physician will be in a better position to outline a patient specific treatment.