纳米硫化铅颗粒亚慢性染毒对大鼠神经行为功能的影响

Effects of nano lead sulfide particulates on neurobehavioral function of sub-chronic exposed rats

目的通过分析纳米硫化铅(PbS)颗粒对大鼠的神经行为变化的影响,探讨不同粒径纳米PbS颗粒对机体的毒性及危害。方法选取体质量为200～240g的清洁级Wistar雄性大鼠24只,按体质量随机分为3组,分别为阴性对照组、PbSⅠ组、PbSⅡ组。对照组灌注生理盐水,染毒组分别灌胃20和26nmPbS颗粒,剂量为50mg/kg,染毒4周后,进行倒挂网格、热板仪、甩尾、Morris水迷宫和后肢撑力实验,以测定大鼠神经系统受损情况。结果倒挂网格实验中,染毒组大鼠的倒挂时间明显短于对照组,且PbSⅡ组最短;对照组大鼠热板实验和甩尾实验中的反应时间均明显短于两染毒组;Morris水迷宫实验中,对照组大鼠找到平台的时间最短,PbSⅡ组大鼠找到平台的时间最长;后肢撑力实验中,PbSⅡ组大鼠后肢分开距离最长,对照组大鼠后肢分开距离最短。结论纳米PbS颗粒对大鼠神经系统功能有一定损害,同时能对大鼠机体造成一定程度的损伤,且粒径越小,损伤越严重。

Objective To explore effects of nano lead sulfide particulates of different diameters on neurobehavior of rats. Methods 24 Wistar male rats were randomly divided into three groups, i. e. PbS I, PbS II and the control groups. Rats in the control group instilled with saline. Rats in exposed groups were administrated PbS ultrafines of 20 nm and 26 nm respectively at the dose of 50 mg/ml for 4 consecutive weeks. Neurological behavior including sensatory（hindpaw--lick latency test and tail throw test）, motor test（hang on gridding test）, hind limb splay test and Morris water maze test was detected. Results Results showed that endurance of hang on gridding of rats of the exposed groups was significantly reduced in comparison with the controls, of which the PbS II group was the shortest. The hindpaw--lick latency and the reaction time of tail throw test of rats of the control group were distinctively shorter than those of PbS exposed groups. In Morris water maze test the time for finding the platform for the control group was the shortest, and that of the PbS II group was the longest. In the hind limb splay test the splay length of rats in PbS II group was the longest, and that of the control group was the shortest. Conclusions Nano--particulate lead sulfide may in certain extent damage the function of the nerve system, and in turn damage the rat body. The smaller is the particulate diameter, the more serious is the damage.