Posted by The HPA-axis (Hypothalamus-pituitary-adrenal axis) is the neuroendocrine system that responds to stressors. Stress can introduce profound physiological implications that are acute as well as chronic. From an evolutionary perspective, a stress response is crucial for survival in harsh conditions to guarantee the passing on of genes during reproduction. The HPA-axis is regulated through a negative feedback cycle. Corticosteroids (cortisol in humans) are hormones synthesized in response to stress. High levels of cortisol inhibit further production through negative feedback. In most cases stress is a necessary response; However, chronically elevated stress hormone levels can have detrimental effects. In humans, long-term increased cortisol levels are linked to a variety of diseases (diabetes, Alzheimer’s, depression, etc.). Chronic stress during early development can have organizational effects on the neuroendocrine system. Low levels of stress/cortisol are beneficial for a newborn, whereas long-term high stress environments can cause hypersensitivity to stress in adulthood. Many of these implications of stress regulated by the HPA-axis are often overlooked. Stress is viewed as a psychological state that arises under “stressful” conditions. Taking a closer look, stress has a deeper meaning and much more far-reaching physiological implications
