Studies on the Significance of Taurine in Radiation Injury

In this experiment, the changes in the urinary excretion of taurine were shown in mice irradiated with a dose producing 80% mortality. The greatest increase in taurine occurred on the first day after irradiation. Thereafter taurine content fell rapidly. During the fourth through the ninth day after exposure, the taurine level in the urine remained lower than the normal amount. From the tenth postexposure day, the level again increased markedly. This elevated excretion ran almost parallel with the increase in the daily mortality rate (based on the fraction of the survivors which die during a given day) of irradiated mice. Various doses of taurine were given to mice at various times after irradiation. The therapeutic effect of taurine in the sense of an increase in the fraction of mice surviving for 30 days postexposure was observed when it was given from the second postirradiation day. The effect was pronounced when it was given on the fourth day after irradiation, at which time the amount of taurine in the urine reached its minimum level. It was also demonstrated that the administration of taurine to irradiated mice promotes the recovery of leukocytes.