Tumor-host metabolic relationships: total levels and chromatographic pattern of vitamin B12 in serum, liver and tumor of Yoshida sarcoma-bearing rats.
Total content of cobalamins was estimated by an isotopic dilution technique in serum and liver of Yoshida sarcoma-bearing rats and in a group of control rats. Total levels of vitamin B12 were also measured in neoplastic tissue. Hydroxycobalamin, adenosylcobalamin, cyanocobalamin and methylcobalamin, were estimated by a chromato-bioautographic technique in the above mentioned tissues and animals. We found no significant difference between control and tumor-bearing rats with respect to the total content of vitamin B12 in the different tissues. This suggests that vitamin B12 requirements of neoplastic cells do not significantly deplete host cobalamin stores. We have also found no significant differences in the values of the different cobalamin coenzyme forms between the two groups of animals. This suggests that there is not preferential uptake of any host cobalamin fraction by the neoplastic cells. The four coenzyme-forms of cobalamin have been detected in Yoshida sarcoma. Adenosylcobalamin and cyanocobalamin are the major components of the pool of cobalamins of the tissue.
D000818:Animals; D003038:Cobamides / Q000378:metabolism; D006879:Hydroxocobalamin / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D051381:Rats; D012517:Sarcoma, Yoshida / Q000378:metabolism*; D014805:Vitamin B 12 / Q000031:analogs & derivatives / Q000097:blood / Q000378:metabolism*
D003038:Cobamides; C019476:mecobalamin; C000913:cobamamide; D014805:Vitamin B 12; D006879:Hydroxocobalamin