Atrial natriuretic peptide (ANP)

Definition

Atrial natriuretic peptide (ANP) is a hormone produced by the heart's atria that helps regulate blood pressure and fluid balance. It promotes sodium excretion, which leads to decreased blood volume and lower blood pressure.

5 Must Know Facts For Your Next Test

1. ANP is released in response to stretching of the atrial walls due to increased blood volume.
2. It acts on the kidneys to increase sodium and water excretion, reducing blood volume.
3. ANP inhibits the release of renin, aldosterone, and antidiuretic hormone (ADH), all of which contribute to increased blood pressure.
4. The primary receptors for ANP are located in the kidneys, adrenal glands, and vascular endothelium.
5. Decreased levels of ANP can be associated with conditions like congestive heart failure where fluid retention is prevalent.

Review Questions

• What triggers the release of atrial natriuretic peptide (ANP)?
• How does ANP affect kidney function?
• Which hormones' activity is inhibited by ANP?

Related terms

Renin: An enzyme secreted by the kidneys that plays a key role in regulating blood pressure through the renin-angiotensin-aldosterone system.

Aldosterone: A hormone produced by the adrenal glands that increases sodium reabsorption in the kidneys, raising blood volume and pressure.

Antidiuretic Hormone (ADH): A hormone released by the pituitary gland that promotes water reabsorption in the kidneys to increase blood volume.