Final Review: Renal Acid/Base Regulation Flashcards
What enzyme is important in the formation of carbonic acid from CO2 & H2O?
Carbonic anhydrase
What is the most important extracellular buffer system in the body?
Bicarbonate buffer system
Increased levels of HCO3- can be excreted by the kidneys resulting in…?
Decrease in blood CO2 levels, therefore, decreased respiration rate
What does the phosphate buffer system play a major role in?
Renal tubular fluid*
Intracellular fluids
What is the main method for removing nonvolatile acids?
Renal excretion
What parts of the renal tubules does H+ ion secretion (via secondary active transport) NOT occur?
Descending & ascending thin limbs of the loop of Henle
Where does primary H+ ion secretion begin?
Late distal tubules & intercalated cells
What does primary H+ active transport involve?
hydrogen-transporting ATPase
Where does ~80-90% of bicarbonate reabsorption occur?
Proximal tubule
What is metabolic acidosis/alkalosis?
Change in plasma pH due to increase (alkalosis) or decrease (acidosis) in bicarbonate ion
In metabolic acidosis, bicarbonate ion is _______ extracellular fluid.
Added to
In metabolic alkalosis, bicarbonate ion is _______ extracellular fluid.
Removed from
What is the lower limit of pH that can be achieved in normal kidneys?
4.5
What is respiratory acidosis/alkalosis?
Change in plasma pH due to increase (acidosis) or decrease (alkalosis) in CO2
How do the kidneys respond to respiratory acidosis?
By adding new bicarbonate ion to extracellular fluid
