What is the primary hormone released by the adrenal glands in response to stress?

The primary hormone released by the adrenal glands in response to stress is cortisol. When the body perceives a stressor, the hypothalamus signals the adrenal glands to release cortisol, which plays a critical role in the body’s stress response. Cortisol helps to regulate metabolism, control blood sugar levels, reduce inflammation, and assist with memory formulation. It is part of the body's complex response mechanisms that prepare it to handle stressful situations, often referred to as the "fight or flight" response.

In contrast, while epinephrine is also released during stress and contributes to the fight or flight response by increasing heart rate and blood flow to muscles, cortisol functions more as a long-term stress hormone. Norepinephrine, like epinephrine, is part of the initial response to stress and helps to prepare the body for immediate action. Insulin, on the other hand, regulates blood glucose levels and does not play a direct role in the body's immediate response to stress.