The in vivo effects of culture medium. I. Radioprotective effects of vitamins, amino acids and inorganic salts of culture medium in mice.

It has been shown that pretreatment of mice with a five-fold condensed culture medium before irradiation increased the number of multipotential haemopoietic stem cells in the spleen. The degree of cyto- and radioprotection is dependent on both the time of administration and the dose of the culture medium. The administration of culture medium in twofold doses in a volume of 1 ml intraperitoneally 18 h and 8 h before irradiation with a dose of 9 Gy protected 95% of C57Bl/6 mice. On the other hand, no therapeutic effect of different doses of the culture medium was found. Our observation suggests that the culture medium can mediate a radioprotective effect. The possible mechanisms participating in this effect are discussed.