[Kinetics of 57Co-cyanocobalamin distribution in the organs and tissues of mice with transplanted tumors]. / Kinetika raspredeleniia 57Co-tsianokobalamina v organakh i tkaniakh myshei s perevivaemymi opukholiami.

The distribution of cobalamin coenzyme precursor, 57Co-cyanocobalamin (57Co-CN-Cbl), in normal animals and in mammary adenocarcinoma (AC 755) and La leukemia-bearing mice has been studied during the exponential phase of tumour growth. The total uptake of radioactivity in the normal target organs was different. AC 755 took up 57Co-CN-Cbl selectively in all the periods of observation. In the case of La leukemia the highest rate of 57Co-CN-Cbl uptake in the spleen was found before its maximal hyperplasia. The accumulation of radioactivity in tumours led to a significant decrease in the total labelled cobalamin levels of the liver and kidneys. Analysis of the obtained kinetic curves revealed a different ability of AC 755 and leukemia cells for utilizing the pool of the endogenous cobalamin.

[Analysis of the cobalamin coenzymes in mouse splenic tumor cells]. / Analiz kobalaminovykh kofermentov v opukholevykh kletkakh selezenki myshei.

Coabalamine coenzymes were studied in tumor spleen cells of mice with La leukosis. Endogenous cobalamines in the cell extracts were separated by two-dimensional thin-layer chromatography and by bioautography. Analysis of the cobalamines ratio was carried out using bioautochromatographic technique. 5-deoxyladenosyl- and methyl cobalamines were found in extracts of the tumor cells.