Introduction
Stress can come in many forms. Stress can be mental, as in preparing to take a test, or trying to figure out how to pay your bills. Stress can also come in physical forms, such as running from a dangerous criminal. Wherever your stress comes from, one gland that plays an important role in dealing with that stress is the adrenal gland.
"Fight or Flight"
Whenever you come under any type of stress, your body responds by activating a process that is often referred to as the "flight or fight" response. This response prepares your body to either fight (such as boosting the immune system in case of injury) or run away (such as increasing the blood flow to the areas responsible for running). All of these actions are fueled by hormones, many of which are produced and regulated by the adrenal gland.
Adrenal Steroids
Adrenal steroids are hormones created by the outer portion of the adrenal glands called the adrenal cortex. These hormones include hydrocortisone and corticosterone, which help regulate the body's response to stress and the "fight or flight" response. Hydrocortisone is the hormone responsible for controlling how the body stores substances such as fat. In stressful situations, the body may use hydrocortisone to increase fat storage so that an emergency energy source is available if needed. Corticosterone prepares the body for any physical damage that may occur during a stressful situation (such as an injury). Hydrocortisone helps suppress inflammation, and prepares the body's immune system for action.
Medullary Hormones
Medullary hormones are produced in the inner part of the adrenal gland called the medulla. These hormones include epinephrine (adrenaline) and norepinephrine (noradrenaline). Epinephrine contributes to the fight or flight stress response by increasing the heart rate, increasing blood flow to the muscles and increasing the conversion of glycogen to glucose (which increases the amount of energy available for the body). All of these functions help prepare the body to run or endure a stressful situation. Norepinephrine contributes to an increase in blood pressure, but is more involved in the emotional feelings felt by stress. An increase of norepinphrine in the brain can create feelings of anxiety, arousal and fear.
