RENAL PHYSIOLOGY-LATE DISTAL TUBULE

SUMMARY

1. The late distal tubule and cortical collecting duct act the same, allowing for further solute and water reab­sorption - regulated by aldosterone and ADH.

2. There are 2 important cell types in the late distal tubule and cortical collecting duct that reabsorb solutes.

3. Principal cells: ATPase counter-transport Na⁺ (into interstitium) and K⁺ (into filtrate); stimulated by aldosterone and hyper­kalemia and inhibited by potassium-sparing diuretics.

4. Intercalated cells: secrete H⁺ (into filtrate) via an ATPase active transport pump; for every H⁺ secreted, one HCO₃^- is reab­sorbed via the action of carbonic anhydrase.

Reference(s)

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