Hypothalamic Pituitary Adrenal Axis

The function of the hypothalamic pituitary adrenal axis plays a key role in physical health. Once it becomes disordered, it will cause great harm to the patient's physical health and will also seriously affect their normal life and work. Therefore, it is particularly important to understand the relevant knowledge and find scientific and effective conditioning methods. People should pay more attention to the hypothalamic pituitary adrenal axis in their daily lives to better ensure their health.

1 The release of CRH from the hypothalamus is influenced by a variety of factors, including stress -- the effect of nerve impulses on the hypothalamus -- the level of cortisol in the blood, and circadian rhythms. For healthy people, cortisol levels rise rapidly after waking up and reach peak blood concentration within 30-45 minutes. Then, cortisol levels gradually decrease throughout the day, rising again towards the evening. During the evening, cortisol levels drop again, reaching their lowest point around midnight. Research has found that abnormal cortisol fluctuations are associated with a variety of conditions, such as chronic fatigue syndrome (MacHale, 1998), insomnia (Backhaus, 2004), and burnout (Pruessner, 1999).

2 From an anatomical perspective, the brain's amygdala, hippocampus and other nuclei are physically connected to the hypothalamus, and this connection allows the brain nuclei to stimulate the HPA axis. The nerve impulses sent by the receptors reach the lateral area of ​​the amygdala through the afferent nerves, and after processing, they are summarized with other information in the cerebral cortex. The central nervous system can project impulses such as fear to different areas of the brain. In the hypothalamus, fear impulses both activate the sympathetic nervous system and regulate the hypothalamic-pituitary-adrenal axis.

When the body is subjected to stressful stimulation, the synthesis of cortisol increases. The increase in the level of this hormone can create a state of readiness, and some of the body's "alert" reactions, such as immune response, will be temporarily weakened, allowing the body to respond to potential dangers at any time.

3 Glucocorticoids have many important functions, such as regulating tension levels; however, excessive amounts of glucocorticoids may cause a certain degree of harm. Hypothalamic atrophy can cause people or animals to be in a state of extreme tension and anxiety. It is generally believed that this phenomenon is caused by long-term high levels of glucocorticoid stimulation. Defects in the hypothalamus impair the body's ability to respond appropriately to stressful stimuli

The HPA axis is involved in a number of neurological mood disorders and functional illnesses, such as anxiety disorder, bipolar disorder, insomnia, post-traumatic stress disorder, attention deficit hyperactivity disorder (ADHD), major depressive disorder, burnout, chronic fatigue syndrome, fibromyalgia, irritable bowel syndrome, and alcoholism. Antidepressants are drugs that mainly target the HPA axis and regulate its functions. They are also conventional and commonly used drugs for treating many diseases.