Changes of somatostatin mRNA positive neuron in hippocampal subfields of lead -exposed rats

To study the changes of somatostatin mRNA(SSmRNA)positive neurons in hippocampal subfields. Wistar rats were exposed to lead by drinking 2 000 μg/ml lead acetate solution for three months, the blood and hippocampal lead concent ration were measured with atomic absorption spectometry,and the number of hippoc ampal SSmRNA positive neurons were observed with in situ hybridization technique .Compared with the control group, lead content of blood a nd hippocampal in lead-exposed rats were obviously higher (P0.05). The n umber of SSmRNA positive neurons in CA 1 area of lead-exposed rats was signifi cantly decreased than that of the control rats(37.60±9.69 vs 53.48±10.22, P0.01);the number of SSmRNA positive neurons in CA 3 area of lead-expo sed rats was less than that of the control rats(16.18±6.19 vs 25.93±7.47, P0.05).[Conclusion]The study suggested that SSmRNA positive neurons have a lower expression in hippocampal subfields of lead-exposed rats.