Accumulation and metabolism of radioactive nuclides

After the injection of RI into the mantle cavity of Iidako (Octopus ocellatus), changes of whole body radioactivity were examined. Both the inorganic and organic forms of cobalt were most heavily distributed in the branchial heart. Cyanocobalamin was distributed in an extremely small amount in the liver, but was more distributed in the arms, or gonad. Mn and Zn were almost equally distributed in most portions, but were scarcely accumulated in the branchial heart. Like Co, Fe was ubiquitous in the branchial heart. In relation to the gel filtration pattern of the branchial heart extract, Co-chloride mostly flowed out into the small molecular zone, and cyano-cobalamin into the heavy molecular zone. Mn, Zn and Fe flowed out into similar portions, and the outflux of protein in absorption spectrum was also similar. Only Co and Fe were concentrated in the branchial heart, suggesting not only that their forms of accumulation were similar, but also that Mn and Zn were present in similar forms. (Chiba, N.)