Adrenal cortex

Definition

The adrenal cortex is the outer layer of the adrenal glands, which are located on top of each kidney. This region is crucial for producing various steroid hormones, including cortisol, aldosterone, and androgens, which play vital roles in metabolism, blood pressure regulation, and stress response. The adrenal cortex functions in tandem with the adrenal medulla, influencing various bodily functions through hormone release.

5 Must Know Facts For Your Next Test

1. The adrenal cortex is divided into three zones: the zona glomerulosa, zona fasciculata, and zona reticularis, each producing different types of hormones.
2. Disorders of the adrenal cortex can lead to conditions like Cushing's syndrome (excess cortisol) and Addison's disease (insufficient hormone production).
3. The adrenal cortex is stimulated by adrenocorticotropic hormone (ACTH) from the pituitary gland, which regulates its hormone production.
4. Hormones produced by the adrenal cortex are essential for maintaining homeostasis during stress by increasing glucose availability and regulating blood pressure.
5. In addition to cortisol and aldosterone, the adrenal cortex also produces sex hormones such as dehydroepiandrosterone (DHEA), impacting sexual development and function.

Review Questions

• How does the adrenal cortex interact with the body's stress response system?
  • The adrenal cortex plays a key role in the body's stress response by producing cortisol, a hormone that helps manage stress levels. When faced with stress, the hypothalamus signals the pituitary gland to release ACTH, which in turn stimulates the adrenal cortex to produce cortisol. This hormone increases glucose availability and suppresses non-essential functions to ensure that energy is directed towards dealing with the stressor, demonstrating how it helps maintain homeostasis.
• What are some common disorders associated with dysfunction of the adrenal cortex, and how do they affect hormone levels?
  • Common disorders associated with adrenal cortex dysfunction include Cushing's syndrome and Addison's disease. Cushing's syndrome results from excessive production of cortisol due to tumors or overactivity of the adrenal glands, leading to symptoms like weight gain and high blood pressure. In contrast, Addison's disease is characterized by insufficient hormone production, resulting in fatigue, weight loss, and low blood pressure. Both conditions significantly disrupt normal hormonal balance and overall health.
• Evaluate the significance of aldosterone produced by the adrenal cortex in maintaining cardiovascular health.
  • Aldosterone plays a crucial role in maintaining cardiovascular health by regulating sodium and potassium levels in the bloodstream. By promoting sodium reabsorption in the kidneys, it helps control fluid balance and blood volume, which directly affects blood pressure. High levels of aldosterone can lead to hypertension and increase cardiovascular risk, while insufficient levels may cause low blood pressure and electrolyte imbalances. Thus, proper functioning of the adrenal cortex is essential for sustaining cardiovascular stability.

Related terms

Cortisol: A steroid hormone produced by the adrenal cortex that helps regulate metabolism, immune response, and stress management.

Aldosterone:

A hormone secreted by the adrenal cortex that regulates sodium and potassium levels in the blood, thus affecting blood pressure.

Adrenal Medulla: The inner part of the adrenal glands that produces catecholamines like epinephrine and norepinephrine, which are involved in the body's fight-or-flight response.