Where in the kidney does active reabsorption of sodium ions occur
Collecting duct
Distal tubule
Ascending limb of Henle
All of the above
Other than at thin descending limb of the loop of Henle, all other sites of tubule Na+ are reabsorbed by various mechanisms.
-        Proximal tubule- 60-70%

Na+- H+ exchange
Na+- Glucose co-transport
Na+- amino acid co-transport
Na+ unitransport

-        The thick ascending limb of the loop of Henle - 30%

Na+- 2Cl-- K+ co-transport

-        Early distal tubule- 7%

Na+- Cl- co-transport

-        Late distal tubule and collecting duct - 3%

ENaC channels