Changes of the expression of neuronal nitric oxide synthase(nNOS)in hippocampus in high-dose lead exposed rats

Objective:To investigate the relationship between the effects of lead on LTP in hippocampus and changes of NOS in subfields of hippocampus.Methods:15 wister rat were fed with 0 2% lead acetate for 3 months and used for high dose lead exposed rats.Lead content of blood and hippocampus were measured by atomic absorption method and immunohistochemical method were used to investigate the changes of neuronal nitric oxide synthase (nNOS) in different hippocampal subfields in lead exposed rat.Results:In compared with control group,the blood and hippocampal lead contents were significantly increased in lead exposed rats(the blood lead content was 150 69±52 14ng/ml vs 5 16±1 15ng/ml,the hippocampal lead content was 1169 27±168 06ng/g vs 199 63±43 14ng/g, P 0 05);the number of nNOS positive neurons(49 56±6 70)in CA1 of lead exposed rats was significantly decreased( P 0 05),as compard with the control(64 56±12 46),but no significant changes were found in CA3.Conclusion:The effects of lead on LTP in hippocampus might be related to the changes of nNOS in subfields of hippocampus in head exposed rats.