Description
Vitamin B12 (cobalamin) is a water-soluble vitamin that plays an important role in the normal functioning of the nervous system and the formation of blood cells. Its deficiency can cause serious changes in the body. Cobalamin in blood serum is bound to two proteins, transcobalamin (TC) and haptocorrin (HC). The transcobalamin-cobalamin complex is called holotranscobalamin (HoloTC), or active B12. A more significant fraction (about 80%) of cobalamin carried by HC (HoloHC) is considered metabolically inactive, as only the liver has cellular receptors for it. Active B12 contains biologically available cobalamin, as only B12 bound to transcobalamin ensures cobalamin access to all cells via specific receptors. Due to the shorter half-life of active B12 compared to HoloHC, a decrease in active B12 levels is one of the earliest markers of cobalamin deficiency.
The active B12 test can be used as a secondary test, after determining total B12 levels, or as a primary one.
Period of execution
Within 6 days. The specified time does not include the day of biomaterial collection