The effect of the experimental lead exposure on expression of nNOS and its gene in the mouse hippocampus

Objective To study the effects of lead exposure on expression of nNOS and its gene in the mouse hippocampus,and quest the molecular toxicological mechanism damaged the learning and memory by lead.Methods Using the reverse transcription-polymerase chain reaction(RT-PCR),as a hamiquantity assay,neuronal nitric oxide synthase(nNOS) mRNA levels in the mouse hippocampus of lead exposure 2,4,8 weeks were investigated.Nicotinamide adenine dinucleotide phosphate reduced state-diaphorase(NADPH-d) histochemistry was used to analyze NOS in the hippocampus of lead-exposed mouse.Results nNOS mRNA presented in the normal mouse hippocampus.Its levels in the hippocampus were distinctly decreased by lead exposure 2 weeks and gradually decreased with lead exposure time increasing.It was detected by the microscoe,that the average number of NOS positive neurons in the normal hippocampus was 57^63±11^5 in the field of vision,but it only was 29^35±9.10 in the hippocampus exposed to lead.Conclusion The expression of nNOS and its gene in the mouse hippocampus could be decreased by lead exposure.