Where in the kidney does active reabsorption of sodium ions occur
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
Collecting duct
Distal tubule
Ascending limb of Henle
All of the above