[Experimental studies on Nicaraven as radioprotector--free radical scavenging effect and the inhibition of the cellular injury].

In the present study, firstly the antioxidant effect of Nicaraven was observed by examining the direct free radical scavenging effect with ESR. Dose dependent effects were shown in scavenging both of superoxide and hydroxyl radicals. In the study to check whether Nicaraven inhibits hydroxyl radical formation or degrades the spin adduct of DMPO with hydroxyl radical, the effect of Nicaraven was suggested that it inhibited hydroxyl radical formation itself. Secondly, it was recognized fluorophotometrically that the inhibiting effect of the agent on the superoxide and hydroxyl radicals promoted damage to benzoate, deoxyribose and some amino acids. The inhibiting effect was nearly the same as that of mannitol. Furthermore, the inhibition of the cellular injury induced by ferrous sulphate was investigated in NIH3T3 cells. The addition of Nicaraven to the cells after 6 hours of reaction with FeSO4, the inhibition of the cellular injury was significant (p < or = 0.01). The effect of Nicaraven was recognized as a radioprotector in vitro. The agent suggested to be able to produce recovery from the damage induced by irradiation at the cellular level.