1. To examine possible regulatory roles of liver and kidney in cobalamin metabolism,
specific activities of the two cobalamin-dependent enzymes, uptake in vivo of cyano [57Co] …

We have studied the intracellular binding of radioactive cobalamin by normal cultured
human fibroblasts grown in medium containing [57Co]-cobalamin. We have also assessed …

The release of 57Co-labelled vitamin B,,([57Co] Bl,) and synthesis of transcobalamin I1
(TCII) by the isolated perfused rat liver were studied 10-42 days after the parenteral …

Cobalamin (Cbl, vitamin B-12) has been extracted and isolated from a number of animal
tissues by using (i) reverse-affinity chromatography on R protein-Sepharose followed by …

In man, use of the general anesthetic nitrous oxide, N2O, is associated with hematologic and
neurologic abnormalities that mimic those seen in cobalamin (Cbl, vitamin B12) deficiency …

1. The purpose of this investigation was to study the appearance and significance of protein-
bound [57 Co] vitamin B 12 in the rat kidney 0.25–4.0 h after intramuscular injection of [57 …

To determine which parts of the cobalamin (cbl) molecule are required for enzyme activity
and which parts, if altered, might inhibit cbl-dependent enzyme activity, we synthesized 16 …

The mechanism of the clearance of vitamin B 12 from the serum transcobalamin II-vitamin B
12 (Tc-II-B 12) complex and the reappearance of free Tc-II in mouse have been studied …

Because the origin of cobalamin (vitamin B12) analogues in animal chows and animal and
human blood and tissues is unknown, we investigated the possibility that multivitamin …

1. This paper reports a survey of values for individual plasma cobalamins in normal subjects,
hospital controls, and patients with vitamin B12 deficiency and diseases in which there are …