Intracellular Distribution of Vit. B 12 -Co 60 in Liver and Kidney of B 12 Deficient and Normal Rats. ∗ †

Abstract

Summary

1) In a study of intracellular distribution of radioactivity of B₁₂-Co⁶⁰, the mitochondrial fraction of livers of B₁₂ deficient rats takes up more radioactivity than does this fraction of normal animals. This increases between 12 hours and 30 days. 2) At 12 hours the supernatant fraction of kidneys of normal and deficient animals is highest in radioactivity, however, at the end of 30 days, radioactivity in the mitochondrial fraction is greatest. 3) There is a transfer of rad ioact ive B₁₂ to liver from extrahepatic sources. 4) Radioactivity of Co⁶⁰Cl₂ is not retained by fractions of tissues as is that of B₁₂-Co⁶⁰.