AIMTo explore the effect of zinc on vigor of nitric oxide synthase (NOS) and the expression level of neuronal nitric oxide synthase (nNOS) in the hippocampus of acute hypoxic mice and the protective effects of zinc.

METHODSModel of acute hypoxic mice was duplicated, NADPH-d histochemistry and nNOS immunohistochemistry were used to investigate the changes of NOS in different groups.

RESULTSCompared with the NS group, the hypoxia endurance of the zinc group was significantly increased; the number of NOS positive neurons and nNOS positive neurons in hippocampus and CA1 were significantly decreased.

CONCLUSIONZinc might play an important role in decreasing the level of NOS in hippocampus to protect the brain against hypoxic damage.