renal acid-base balance lecture

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Week 6, Lecture
Renal Acid-Base Balance
Acid-base balance
 Describes pH
 Can be acidic or alkaline
 Blood pH
o Very tight
o 7.34-7.38
o Must be kept in balance
o Venous and arterial blood can be at either side of the spectrum
 Gastrointestinal tract is very acidic as it has a specific function
o Lose a lot of acid through vomiting
 Acid can donate protons
o Increase in H pH will fall, and acidity will rise
 Bases accept protons
o Decrease H pH rises acidity falls
Buffer systems
 Can adapt to changes in pH
 Prevent major changes in pH
 Can bind to and release hydrogen ions when needed
 Regulated by
o Chemical buffers
o Respiratory centres
o Renal system
Acids are being created constantly
 Acids come from food
 Metabolism
o From breakdown through respiration
 Meets blood system
 Proteins can act as a buffer for hydrogen ions
 Lungs can increase or decrease ventilation
 Kidneys release excess hydrogen ions
Buffering systems
 Respiratory system
o Bicarbonate
 Blood
o Bicarbonate
o Phosphate
o Proteins
 Kidneys
o Bicarbonate
o Phosphate
o Ammonia
Phosphate buffer systems
 Intercellular
 Renal tubular buffer
 Concentration in plasma low