Adrenal medulla

Definition

The adrenal medulla is the inner part of the adrenal glands, which are located on top of each kidney. It is responsible for producing hormones like epinephrine (adrenaline) and norepinephrine (noradrenaline) that play a crucial role in the body's fight-or-flight response. These hormones help prepare the body for quick action during stressful situations by increasing heart rate, blood pressure, and energy availability.

5 Must Know Facts For Your Next Test

1. The adrenal medulla releases epinephrine and norepinephrine into the bloodstream during times of stress, which leads to increased alertness and energy.
2. The activation of the adrenal medulla is part of the sympathetic nervous system response, which prepares the body to react quickly to perceived threats.
3. Epinephrine acts on various receptors throughout the body, causing effects such as increased heart rate, elevated blood sugar levels, and enhanced blood flow to muscles.
4. The adrenal medulla's secretion of hormones has a relatively short duration compared to the long-lasting effects of hormones produced by the adrenal cortex.
5. Dysfunction in the adrenal medulla can lead to disorders such as pheochromocytoma, which is characterized by excessive production of catecholamines.

Review Questions

• How does the adrenal medulla contribute to the body's response to stress?
  • The adrenal medulla contributes to the body's stress response by releasing hormones like epinephrine and norepinephrine into the bloodstream. These hormones increase heart rate, elevate blood pressure, and mobilize energy stores, effectively preparing the body for rapid action. This process is essential during stressful situations where quick responses are necessary for survival.
• Compare and contrast the roles of the adrenal medulla and the adrenal cortex in hormone production and their effects on the body.
  • The adrenal medulla primarily produces catecholamines such as epinephrine and norepinephrine, which are crucial for immediate stress responses. In contrast, the adrenal cortex produces corticosteroids like cortisol that regulate longer-term stress responses, metabolism, and immune function. While both parts of the adrenal glands play important roles in how the body responds to stress, their functions and effects differ significantly in terms of duration and physiological impact.
• Evaluate how dysregulation of the adrenal medulla can affect overall health and wellness.
  • Dysregulation of the adrenal medulla can lead to conditions such as pheochromocytoma, resulting in excessive production of catecholamines. This can cause symptoms like hypertension, anxiety, and heart palpitations, impacting overall health. Moreover, chronic overactivity or underactivity can disrupt normal physiological processes, potentially leading to serious health issues including cardiovascular disease and metabolic disorders. Understanding these impacts is essential for effective treatment strategies.

Related terms

epinephrine: A hormone produced by the adrenal medulla that increases heart rate, dilates air passages, and is involved in the body's fight-or-flight response.

norepinephrine: A hormone and neurotransmitter produced by the adrenal medulla that works alongside epinephrine to regulate arousal and stress responses.

adrenal cortex: The outer layer of the adrenal glands that produces different hormones such as cortisol and aldosterone, which are involved in stress response and metabolism.