Role of Calcium Channels in the Fight or Flight Response

During the design and evolution of early hominids, a response to prevent early human ancestors from being eaten by the much larger and ferocious predators of that day was developed.  Known today as the “fight or flight response”, this hardwired signal to oncoming danger has helped prepare humans from becoming a meal for prehistoric animals as well an an aid in early battles to present day wars.  For the majority of humans who live in the safety of houses or other accommodations where threats of animals attacking are relatively unheard of, the fight or flight response has become a primitive throwback to our humble and dangerous beginnings.  The threats that most people encounter nowadays are in the form of losing jobs and financial security or dealing with the stress of juggling busy jobs and personal lives.  Like other hardwired and primitive brain actions, the fight or flight response to stress cannot simply be turned off.  Knowing what occurs in the body during the fight or flight response does give a basic understanding as to why the body reacts to stress in such a dramatic way. 

When the brain activates the fight or flight response, a number of inner and outer physical changes occur.  Inside the body, the blood vessels and arteries constrict and prevent blood from flowing to the stomach and other organs that may be currently in the process of food digestion and the blood is redirected to the muscles of the arms and legs. When this happens, any food in the stomach or intestines will be left undigested causing the person to vomit or have diarrhea.  Another physical change is an increase of the heart rate and sweating of the palms and other areas of the body as stress hormones are released into the bloodstream.  All of these physical actions prepare the person for a rush of energy to either run as fast as possible from the oncoming danger or stand up and fight it. 

While this system worked wonderfully for primative humans confronting a wooly mammouth or another group of people battling for territory, modern humans who activate this response become even more stressed as they are not able to use this response for its intended purpose.  Stress causing situations begin to hurt the body over time due to the way stress hormones are not properly disposed of after the fight or flight response has been activated numerous times.  During an actual fight or flight, the stress hormones are removed from the blood by the physical activities performed by the charged up muscles.  Running or using to the body to defend itself physically allows the muscles to consume the hormones. 

Another problem encountered from this response is the role that calcium channels play in the fight or flight response.  Calcium channels are known well in the world of cardiac health for their role in constricting blood vessels.  In the fight or flight response, calcium channels pump calcium ions into the blood leading to the muscles which causes them to contract.  This helps the muscles respond quickly to the threat stimuli and allows the human to get up and run away or kick and punch in defense.  But when fighting or running away will not help the situation, excess calcium in the blood and muscles can cause other problems for the already stressed out individual. 

Calcium blockers are a type of drugs used to treat patients with cardiac health problems such as high blood pressure and hypertension.  These drugs block the flow of calcium ions into the blood to prevent the blood vessels from contracting and constricting.  High blood pressure is a common side effect of chronic stress and is a dangerous health concern as it can lead to heart attacks and strokes. 

The role of calcium channels in the fight or flight response is highly beneficial for those who actually encounter a truly threatening situation where the only options are to be physically active in one form or another.  Unfortunately, this rarely translates to modern day situations where the threatening situation cannot be resolved by running away or punching someone.  This response evolved and developed in humans as a way to continue the species and is present in the majority of the population.  Without it, humans would not have survived to this day.  The problem is, how can this response be switched off during times when the need to become physical will never be necessary?  The solution is easier said than done: try to avoid stressful situations.