Aldosterone

BACK TO DISTAL TUBULE

Overview

• Steroid hormone
• Secreted from the zona glomerulosa of the adrenal cortex of the adrenal gland
• Mineralocorticoid
• Most important regulator of plasma pottassium
• Stimulated directly by increased plasma pottassium
• Also stimulated as part of the Renin-Angiotensin-Aldosterone System (RAAS)

Action

• Works by altering gene transcription
  • Affects ATP levels

Sodium

• Affects sodium entry and transport
• Increases sodium re-uptake to a small degree in distal convoluted tubule

Pottassium and Hydrogen

• Causes pottassium and hydrogen secretion
  • Pottassium via apical leak channels
  • Hydrogen by proton secretory proteins