Acid Base physiology

Question 1

Once H2O + CO2 inside the cell is converted by intracellular carbonic anhydrase it is HCO- & H+. The hydrogen leaves on what side and by what transporters?

Answer 1

In the PT H+ leaves on the apical side via active transport by the :
Na/H anti porter
H+ pump (pushes back into lumen)

In the TAL:
H+ leaves mainly by the H+ pump

in the MCD:
H+ leaves mainly the K/H transporter

Question 2

How does bicarbonate get out of the cell and into the interstitial/blood?

Answer 2

HCO- exits the basolateral side by :
Na/HCO- symporter
HCO-/Cl exchanger