acid excretion Flashcards
what are the 2 acids made by the body ?
one is called volatile acids an non volatile acids
what are the volatile acids made by the body and how are they excreted ?
1- carbon dioxide
combines with water to form carbonic acid and hydrogen which is then eliminated by the lungs
2- sulfuric acid
sulfuric acid then binds to bicarb and is excreted by the kidneys and the lungs
why is there no change in pH with the production of sulphuric acid ?
because as long as there is bicarb production there is buffering of the acid and hence no change in pH
generally speaking what are the 2 methods in which the kidneys perform acid base regulation ?
1- through reabsorption and generation of bicarb
2- through the excretion of hydrogen
what are the methods of bicarb reabsorption in the kidney ?
this mostly happens due to the PCT cells , where there is an exchange of protons for sodium , with the use of carbonic anhydrase , gowa and inside the cell
what is the percentage iof bicarb secreted by the kidneys ?
0 all of it must be reabsorbed
where is the production and generation of bicarb happening ?
in the intercalated cells of the collecting duct
where co2 and h2o are joined together to make hydrogen and bicarb with the enzyme carbonic anhydrase
hco3 are reabsorbed into the interstitium
what are the bi products of bicarb production ?
hydrogen ions are produced as a side product and must be excreted in the urine
what are the buffers made used to neutralize the effects of the H produced in bicarb production ?
titratable acids - mostly phosphates
ammonia
what is the association between the levels of hydrogen and the levels of phosphate ?
increased hydrogen excretion is associated with increased dihydrophosphate excretion
where is ammonia synthesized from ?
synthesized from glutamine
where does most of the bicarb reabsorption happen ?
in the PCT
how do you calculate the net acid excretion ?
titratable acids plus NH4 minus HCO3
what are the levels of net acid excretion in acidosis vs alkalosis ?
in acidosis there is increased net acid secretion and decreased in alkalosis
