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)
Wilkinson, I. (2017). Oxford handbook of clinical medicine. Oxford: Oxford University Press.
Hannaman, R. A., Bullock, L., Hatchell, C. A., & Yoffe, M. (2016). Internal medicine review core curriculum, 2017-2018. CO Springs, CO: MedStudy.
Therapeutic Guidelines. Melbourne: Therapeutic Guidelines Limited. https://www.tg.org.au [Accessed 2021].
