ABSTRACT
OBJECTIVE@#To study the mechanisms of cultured neurons injury mediated by nitric oxide and free oxygen radical during hypoxia and oxidative stress.@*METHODS@#The cultured newborn rat neurons were treated with hypoxia, H2O2 and pretreated superoxide dismutase (SOD) respectively. We examined the content of NO, malonaldehyde (MDA), lactate dehydrogenase (LDH) and SOD in cultured supernatant.@*RESULTS@#Comparing with that of control group, the content of NO, LDH, MDA increased and the content of SOD decreased in hypoxia group and H2O2 group. The content between NO and SOD showed the negative correlation. Administration of 200 U/ml SOD before oxidative stress could efficiently decrease the release of NO, LDH and MDA in neurons. The content of NO, LDH and MDA manifested in positive correlation in each group.@*CONCLUSION@#Hypoxia and oxidative stress increased NO production which strengthen neurons injury induced by free radical. SOD played an important role in elimination of free oxygen radicals and protecting neurons from injury by NO.