Vitamin B12 Deficiencies -2
Bound
to haptocorrin in saliva
Trypsin
causes haptocorrin to release B12 in small intestine
B12 then bound to intrinsic factor
Impaired absorption:
Mechanism
of absorption:
intrinsic factor produced
by gastric
parietal cells
B12 - intrinsic factor complex then binds to
receptors on ileal cells and passes into plasma
B12 then bound to:
Haptocorrin – inactive
form
Transcobalamin II –
active form
majority
minority