Abstract: Objective To study the protective effects of the compound with low molecular weight of anti free radical on brain ischemic and hypoxic injuries in rats.Methods The model of brain ischemic and hypoxic injuries in rats was established by unilateral carotid artery ligature just for 2 h. The compound was injected 30 minutes after the rats act on hypoxic state (10% O₂+90%N₂) for 1 h. Then the serum of rats was separated and the value of the superoxide dismutase (SOD) activity and malondiade (MDA) were determined, and the pathological changes were observed in brain tissue.Results Compared with rats in the model group, the compound decreased the concentrations of MDA in serum (P<0.05), and raised the level of SOD (P<0.05) significantly in therapy group. Otherwise, the pyramidal cells remained organized order, with only a few cells degenerated occasionally in rats of therapy group. Conclusion The compound has SOD like activity. It can scavenge the free radical and inhibit peroxidation of lipid, so it can prevent brain cells from the damage.

Key words: radical, brain injury, superoxide dismutase (SOD), malondiade