Hormones play a significant role in regulating behavior. The brain is the controlling center for the release of most hormones, including stress hormones such as cortisol and norepinephrine. Stress causes the pituitary gland in the middle of the base of the brain to release ACTH (another hormone), which in turn stimulates the adrenal cortex. The release of hormones is regulated by the endocrinal system.
The term "stress" is confusing, as it is often used to define both the stress response and the stressor. Stressors are stimulating factors that bring about a stress response. A stress response includes aspects like a change in metabolism, physical and mental state, and a sudden surge in energy.
Cortisol is a corticosteroid that is produced by the adrenal cortex in the adrenal gland. It is often referred to as a stress hormone, as it is released in response to stress. Its increased production leads to high blood pressure, increased levels of blood sugars, and inhibits the immune system.
Norepinephrine, on the other hand, is a catecholamine that functions both as a hormone and neurotransmitter. Norepinephrine is synthesized from dopamine, a neurotransmitter, and released from the adrenal medulla in the blood. In the brain, it is released by noradrenergic neurons and acts as a neurotransmitter in the central and the sympathetic nervous systems. As a stress hormone, norepinephrine affects those parts of the brain that are responsible for attention and responding to actions. In conjunction with epinephrine, it forms the basis of the fight-or-flight response (stress response) by directly increasing the heart rate, stimulating the release of glucose from stored energy, and enhancing the supply of blood to skeletal muscles.
Cortisol and ACTH are released not only in response to a stressor. Both ACTH and cortisol are released daily according to the circadian rhythm. The ACTH precedes the change in levels of cortisol, which is normally high in the morning. This is normal and helps in preparing you to meet minor challenges during the course of the day.
Stress is one of the major causes behind psychological disorders like anxiety and depression, and it is believed that serotonin and norepinephrine are clearly involved in depression. A new theory is emerging that suggests that stress hormones also play an important role in causing emotional disorders.
Increased ACTH secretions and prolonged high levels of cortisol in response to constant stress affect your overall health because the fight-or-flight response is supposed to be a transient phase only to meet a threat. Constant stress means that the body does not return to its normal state that it is supposed to be in.
Managing stress in your life is thus important to remain in healthy mental and physical condition. Small amounts of stress are normal in daily life due to the hectic lifestyle that we have evolved into, and mild stress is also necessary to reach peak performance. Constant stress, however, is something that you have to manage. Look for effective natural stress relief measures like relaxation, meditation and yoga. Acceptance of the inevitable and positive thinking can help in removing stress from your life permanently.References: