Atrial Natriuretic Peptide (ANP)

Relationship of Fluid Volume and Blood Pressure

• Fluid volume changes impact blood volume.
• Blood volume alterations affect blood pressure.

Function of ANP

• ANP is a hormone secreted by the heart's atria.
• Helps control blood pressure.

Triggers for ANP Secretion

• Secreted in response to increased blood volume.

Mechanism of Action

• Target: Kidneys
  • Decreases sodium reabsorption.
  • Increased sodium excretion leads to:
    • More water exiting the body by osmosis.
    • Decrease in fluid volume.
    • Reduction in blood volume and blood pressure.
• Effect on Blood Vessels:
  • Causes vasodilation.
  • Lowers blood pressure.
  • Vasodilates afferent arteriole, increasing kidney filtrate production.
    • Enhances sodium and water excretion by kidneys.

Additional Effects of ANP

• Inhibits renin-angiotensin system.
• Reduces aldosterone secretion by the adrenal cortex.
• Promotes release of free fatty acids from adipose tissue.

Understanding ANP helps in grasping how the body regulates blood pressure and fluid balance.