Learning Objectives
- Describe the reabsorption of filtered bicarbonate by the proximal tubule
- Discuss how bicarbonate is excreted in response to an alkaline load
- Describe how the renal tubule generates new bicarbonate
- Describe how the kidneys handle ammonium that has been secreted in the
proximal tubule
- Describe how the excretion of ammonium accomplishes the goal of excreting acid
- Describe the kidney response to acid-base disorders
Renal Acid Base Physiology
- what is the role of the renal system in acid base balance?
- what would happen if bicarbonate was not fully reabsorbed?
- where is $H^+$ secreted/ where is $HCO_3^-$ reabsorbed?
- what effect do carbonic anhydrase inhibitors have on this?
- what is the ‘limiting pH’ that inhibits $H^+$ secretion?
- what 3 mechanisms is $H^+$ secreted by?
- what buffers are involved in renal acid base balance?
- what is the role of the phosphate buffer in $H^+$ excretion?
- what is the role of the ammonia buffer in $H^+$ excretion?
- how is ammonium excretion regulated?
- despite the buffer systems, why is urinary pH still low?