ADRENALINE AND HOW IT AFFECTS US
Having exhausted all I could remember for the examination, I was now staring at the ceiling expecting manna to fall from there. I was on this routine stare when my eyes caught the eagle eyes of the invigilator scrutinizing me. At that instant, just like magic, I remembered all I read. Then, there was the increased heartbeat, the contracted muscles, the raised hairs on the surface of my skin and the intensified breathing. I knew my adrenaline was in action but I cared less as I scrambled all that I remembered in a jiffy. It was after the examination that I wondered, “How does this miraculous adrenaline work?”

Olamide would say; “first of all, introduction”. Adrenaline is a hormone that is secreted by the adrenal glands situated above the kidneys. This adrenal gland secretes not only adrenaline, but also noradrenaline and other corticosteroid hormones. Adrenaline is also known as epinephrine. I am not going to bother us with other corticosteroids as I am concentrating on my examination-helping corticosteroid (adrenaline).

What Role Does Adrenaline Play in the Body?
Adrenaline as most of us know is involved in the “fight” or “flight” response in humans. This response occurs when a person is subject to a threat. This causes a signaling process to occur, which causes the body to react to the potential danger (my invigilator’s scrutinizing eyes).
Specifically, once a threat is perceived, a text message (signal) is sent to the brain, the brain then sends nerve impulses to the adrenal gland in the kidneys. When these nerve impulses reaches the adrenal gland, chromaffin cells in the medulla of the adrenal gland, releases our friendly hormone, adrenaline. Adrenaline then enters the body’s blood stream and is carried around the body to cells in various locations, where it initiates several responses.
Despite initiating several different responses, adrenaline’s effect have a collective purpose which is to provide energy so that the major muscles of the body can respond to the perceived threat.
Now, Nigerian students, let’s talk about the different avenues of response…

Adrenaline and Liver Cells
Among the places where adrenaline has an effect is in the liver. Adrenaline, along with another hormone, glucagon, is responsible for the breakdown of glycogen in liver cells. Glycogen is a form of energy storage in animals including you.

Adrenaline and the Skin
The effect of adrenaline on the skin is caused mainly by its binding to some nerve cells (alpha-2-adrenergic receptor in particular). This causes the arteries (ie blood vessels carrying blood away from the heart) to restrict, thus, cutting off blood supply to the skin. A signaling cascade (process) is also stimulated which eventually results in the contraction of the smooth muscle cells in the skin. This causes the raising of the hairs on the skin surface.

Adrenaline and the Lungs
The lungs contain smooth muscles. Adrenaline causes smooth muscles to relax. Specifically, adrenaline binds to some nerve cells (beta-2-adrenergic receptors in particular) on bronchioles muscle cells. This allows the bronchioles to relax, thus causing intensified respiration (breathing).

Adrenaline and the Heart
Adrenaline binds to beta-adrenergic receptors on heart muscle cells. This causes the contraction rate of the heart to increase. This leads ultimately to increased blood supply to the tissues in the body and to the brain. This increased blood supply to the brain enhances brain activity or functioning.

All these different responses in a second come together to achieve one purpose, and that is providing energy so that the major muscle of the body can respond to the perceived threat. This therefore leads you to either fight (if you are me) or flee (if you are you).