Atrial natriuretic peptide

Definition

Atrial natriuretic peptide (ANP) is a hormone produced by the heart's atria that regulates blood pressure and fluid balance. It promotes sodium excretion and diuresis, reducing blood volume and pressure.

5 Must Know Facts For Your Next Test

1. ANP is released in response to atrial stretch due to increased blood volume.
2. It acts on the kidneys to increase glomerular filtration rate (GFR) and inhibits sodium reabsorption in the renal tubules.
3. ANP opposes the actions of the renin-angiotensin-aldosterone system (RAAS).
4. It also relaxes vascular smooth muscle, leading to vasodilation.
5. Elevated levels of ANP can be indicative of heart failure or other cardiovascular conditions.

Review Questions

• What triggers the release of atrial natriuretic peptide?
• How does ANP affect kidney function?
• Which hormonal system's actions are opposed by ANP?

Related terms

Renin-Angiotensin-Aldosterone System (RAAS): A hormone system that regulates blood pressure and fluid balance.

Diuretics: Medications that promote diuresis, or increased urine production.

Glomerular Filtration Rate (GFR): The rate at which blood is filtered through the glomeruli of the kidney.