PROTECTIVE ROLE OF SUPEROXIDE-DISMUTASE IN CHICK AMNIOTIC-FLUID DURING RADIOTHERAPY

Superoxide dismutase (SOD) activity was regularly assayed in the fract ions of chick amniotic fluid and whole embryonic tissue from the sixth to the twelfth day of embryo development. The results showed a linear increase in the enzyme activity with the development, which may play a role in the organogenesis of embryo. Chick embryos were exposed to d ifferent doses of X-irradiation (1,000, 3,000 and 5,000 Roentgens) on the ninth day of development. After 24 h SOD levels were measured in b oth the amniotic fluid and whole embryo. The activity increased signif icantly with the dose of 1,000 R and above in both fractions of amniot ic fluid and in embryonic tissue. To study the post-irradiation time e ffects(-)(1 h, 48 h and 72 h) on SOD activity the eggs were exposed to a 1,000 R dose on day 9 of development. The percent of change decreas ed as the post-irradiation period advanced.