Another important hormone released by the pituitary gland is adrenocorticotropic hormone (ACTH). When ACTH is released into the blood stream, it is picked up by the adrenal glands—the two glands sitting on top of the kidneys. The adrenals also have many functions, two of which involve the stress response, the release of the fight or flight chemicals (epinephrine, norepinephrine), and the production of cortisol, which—in addition to being a response to stress—also involves the release of blood sugar, suppression of the immune system, and the metabolism of fat, protein, and carbohydrates.
The adrenal glands’ role in the production of cortisol and the stress hormones epinephrine and norepinephrine is important. These are the major players when it comes to the difference between those of us who get sick and those who do not (Kemeny, 2010).
The HPA axis—the hypothalamus, pituitary, and adrenal—forms the mind-body connection. These systems function as feedback centers, continuously monitoring and communicating what is going on in the brain and body and how it should respond.
This axis is critical to survival, releasing controlled levels of hormones in the right doses at the right times and maintaining balance in the body by regulating crucial body functions. However this system can be detrimental to our health when it gets out of balance, being over- or under- stimulated.
We all have experienced over-stimulation of this system. Just think back to the last time you were in traffic, and the driver from Hades appeared out of nowhere. He crossed your path, causing you to perform some fancy maneuvers to avoid hitting him and to dodge the car in the next lane. Unless you are in zombie land, your body did what every human body does. Immediately you went into a fight-flight stress response, an automatic nervous system response triggered by the HPA axis.
You more than likely felt as if your heart was going to jump out of your chest; this is because your heart rate and blood pressure increased. Mentally you were more alert because you needed to think critically, weighing your options in this emergency. At the same time your energy stores were being mobilized, giving you a surge of energy due to increased blood sugar levels. You started breathing faster, your pupils dilated, and you felt shaky and nervous. All this happens extremely fast—within milliseconds!
This is the brain and hormonal chemical response, but what about the immune system? How does it fit into the equation and cause disease?
The Immune System
God made provision for the body to defend itself when invaded by unwelcome guests. These uninvited visitors come in many forms: viruses, bacteria, and parasites to name a few. And the immune system, the defender of the body, is waiting at the door, ready to go to battle.
Similar to a military’s SWAT team, the immune system has special weapons and tactics enlisted to fight the body’s battle. The major players are WBC’s, T-cells, B-cells, Natural Killer Cells, monocytes, and the macrophage (Goodman, 2004). These immune cells are located all over the body and lay in wait to pounce on unsuspecting intruders.
Their response to invaders reminds me of an attempted robbery gone awry. Remember those old funny movies with the clumsy robber dressed in black? He’s wearing a mask, and he’s carrying a sack on his back to collect the loot. He stealthily climbs to his destination and is ready for the steal, but along the way he is bitten, clubbed, stabbed, chased, beaten, and then arrested. This is what the immune system does to unwelcomed guests.
This highly sophisticated system has soldiers strategically stationed, and their lookout posts cover the entire body—lymph nodes, liver, spleen, stomach, and lungs. Even our tears, sweat glands, and saliva contain chemicals that neutralize invaders.
Inflammation
But before the immune system can mount a response, it must be turned on. Turning on occurs in response to injuries or damage to the body. We can injure the body in a variety of ways, such as physical injuries (which can occur in the form of extreme temperatures), environmental toxins (like radiation exposure), and nutritional imbalances to name a few. Injuries also come as foreign invaders—parasites, viruses, and bacteria.
Foreign invaders can also come in the form of chemical toxins, splinters, or glass to the body. Just think back to the last time you stubbed your toe, had a sliver of glass under your skin, or perhaps suffered a superficial wound. More than likely you noticed redness and swelling which were due to local inflammation. However, there is also inflammation that we cannot see, and it affects organs throughout the entire body. Organs such as the heart, lungs, brain, connective tissues, and other vital systems encounter inflammation, which causes the same damage, but it is beneath the surface. It is in the presence of injury and inflammation that the immune system mounts a defense and comes to the rescue (Goodman, 2007b).
Right about now you might be saying—brain, hormones, immune system, and this HPA thing, okay, but how does this relate to disease, and why should I be concerned? Remember Karen? When we look back at her life, we see that it was one of constant chaos in which she suffered from psychological stress, and then later physical symptoms, which progressed to disease. When we look at her case from the mind’s point of view, there emerges a picture of how the mind and body link and lead to disease.
Let’s Connect the Dots!
Karen was in a bad relationship! From the time she got up, until she went to bed, she was hearing: “You’re stupid,” “You’re fat,” “Can’t you do anything right?” and “Why did I marry you?” These negative messages activated the HPA axis, which triggered the release of cortisol and the fight or flight response. These two systems are wonderful and imperative in emergencies such as outrunning an attacking dog, fleeing an intruder, dodging bullets, and—as in our earlier example—helping with the response time in near car accidents. But the constant increased activation of cortisol and fight or flight response has profound negative effects on the body.
The stress hormone cortisol is absolutely needed in order for the body to function efficiently. It is when the body is being bombarded with constant surges of cortisol that it becomes counterproductive. In the presence of high cortisol levels, the immune system’s ability to function is suppressed; therefore, it can no longer do its job of protecting the body from invaders. Not only does cortisol depress immune function, but an elevated cortisol level increases inflammation, increases blood sugar levels, decreases the ability of DNA to make repairs, destroys brain cells, causes scars in the lining of the blood vessels, and can confuse the immune system, causing it to turn on itself (Sapolksy, 1985; Wolkowitz, 2010; Kemeny 2010).
The autonomic nervous system—fight-flight—puts the pedal to the metal when it releases the stress hormones epinephrine and norepinephrine. As stated earlier, it increases the blood pressure and heart rate, suppresses the immune system and other organs, mobilizes fat stores (fat deposits in the blood vessels), and causes an increase in blood sugar levels (for extra energy). This response is also needed in an emergency; however, chronic activation of this fight or flight response lays the foundation for disease in the form of heart disease, diabetes, stroke, obesity, among many others.
As indicated, Karen was healthy prior to her relationship, but after being beaten down and degraded for so many years, she believes that her horrific marriage led not only to her heart disease but also to other physical ailments as well as mental depression. Looking at her case from the mind’s point of view, when we connect the dots, we must ask: is there a mind-body connection? The research coming out strongly suggests that there is. We have seen a clear line in which the mind, hormones, and immune system—psychoneuroimmunology—connect and under adverse conditions can lay the foundation for the development of disease.
Like Karen, many find themselves