Question

How do the kidneys help to correct acid-base imbalance. Please be sure to include reference for your answer

Answer 1

kidneys regulate pH by allowing the reabsorption or elimination of hydrogen ions. They are responsible for long-term pH regulation. More acids than bases enter the blood, so the kidneys mostly eliminate acids than bases. Thus, the urinary pH is usually acidic.

The bicarbonate buffer system involves an acid and base homeostatic mechanism further involving the equilibrium balance of carbonic acid (H₂CO₃), bicarbonate ion (HCO₃^-), and carbon dioxide (CO₂) in order to maintain isotonic pH (7.4).

This reaction is catalyzed by the enzyme carbonic anhydrase. The carbon dioxide (CO₂) reacts with water (H₂O) to form carbonic acid (H₂CO₃).This in turn rapidly dissociates to form a hydrogen ion (H⁺) and bicarbonate ion (HCO₃^-) as described in the following reaction.

CO2 +H,0 AH,CO, H* + HCO3

The excess hydrogen ions are eliminated by the kidneys to main the appropriate pH levels. Excessive exhalation of carbon dioxide by increased rate of respiration also helps in raising the pH to the normal level.

Reference:

Hall, J. E. (2010). Guyton and Hall Textbook of Medical Physiology: Enhanced E-book: Elsevier Health Sciences.