铅对大鼠海马和大脑皮质NOS活性的影响

The Effect of Experimental Lead Exposure on Activity of NOS in the Rat Hippocampus and Cerebral Cortex

目的 观察实验性铅中毒对大鼠海马和大脑皮质一氧化氮合酶（NOS）性的影响，探讨NOS在铅中毒中枢系统损害中的作用机制。方法 4周龄Wistar雄性大鼠按45mg/kg剂量行醋酸铅灌胃30d；大鼠海马和大脑皮质总NOS和诱导型一氧化氮合酶（iNOS）活性测定采用NOS催化L-Arg和氧分子生成NO法。结果 与空白对照纽大鼠比较，染铅组大鼠海马和大脑皮质总NOS活性明显降低，而iNOS活性均升高，差异有显著性（P〈0．01）。结论 铅可以使大鼠海马和大脑皮质总NOS活性降低，iNOS活性升高。

Objective To study the effect of experimental lead exposure on activity of NOS in the rat hippocampus and cerebral cortex, and to explore the role of NOS in the neurotoxic mechanism of lead. Methods Four weeks old male Wistar rats were exposed to lead by intragastrie administration with 45 mg/kg （body weight） lead acetate for 30 days. The activity of total NOS and iNOS enzyme in hippocampus and cerebral cortex were determined by NOS catalyzing L - Arg into NO. Results The activity of total NOS enzyme was dramatically suppressed in both hippocampus and cerebral cortex, but the activity of iNOS was dramatically increased. Conclusion The enzyme activity level of NOS in the rat hippoeampus and cerebral cortex can be decreased but iNOS activity increased by lead exposure.