Abstract
The plasma binding of newly absorbed, radioactively labelled vitamin B12 was studied during a urinary excretion (Schilling) test. Vitamin B12, after being absorbed from the gut, enters blood attached to transcobalamin II, which seems to be derived from the ileal enterocyte. The absorbed B12 re-enters the blood stream after the transcobalamin II-B12 complex is cleared by the liver and it is then excreted into the urine during the Schilling test.
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Selected References
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- Begley J. A., Hall C. A. Measurement of vitamin B12-binding proteins of plasma. I. Technique. Blood. 1975 Feb;45(2):281–286. [PubMed] [Google Scholar]
- England J. M., Clarke H. G., Down M. C., Chanarin I. Studies on the transcobalamins. Br J Haematol. 1973 Dec;25(6):737–749. doi: 10.1111/j.1365-2141.1973.tb01786.x. [DOI] [PubMed] [Google Scholar]
- Hom B. L. Plasma turnover of 57cobalt-vitamin B12 bound to transcobalamin I and II. Scand J Haematol. 1967;4(5):321–332. doi: 10.1111/j.1600-0609.1967.tb01633.x. [DOI] [PubMed] [Google Scholar]
- Peters T. J., Hoffbrand A. V. Absorption of vitamin B 12 by the guinea-pig. I. Subcellular localization of vitamin B 12 in the ileal enterocyte during absorption. Br J Haematol. 1970 Sep;19(3):369–382. doi: 10.1111/j.1365-2141.1970.tb01634.x. [DOI] [PubMed] [Google Scholar]