出生后早期接触功夫菊酯对仔鼠大脑突触蛋白表达的影响

Effects of postnatal lambda-cyhalothrin exposure on synaptic proteins in ICR mouse brain

目的 观察出生后早期功夫菊酯（LCT）染毒对ICR仔鼠不同脑区突触蛋白表达的影响.方法 健康清洁级ICR小鼠按2∶4（雄∶雌）合笼受孕,出生小鼠每窝随机分为5组,分别为0.1、1.0和10.0 mg/kg LCT染毒组及溶剂对照组（0.01%二甲亚砜）和生理盐水对照组,每组雌雄各4只,仔鼠出生当天为出生后第0天（PND 0）,PND5开始灌胃染毒,隔天1次,连续5次,PND14取材.蛋白质印迹法检测皮层、海马、纹状体突触蛋白的表达.结果 与溶剂对照组比较,各染毒组雄性仔鼠和10.0mg/kg组雌性仔鼠海马组织及1.0、10.0 mg/kg组雄性仔鼠和10.0 mg/kg组雌性仔鼠皮层胶质原纤维酸性蛋白（GFAP）表达升高,差异均有统计学意义（P＜0.05）,且有剂量相关性（雄性：r海马=0.986,r皮层=0.945;雌性：r诲马=0.993,r皮层=0.969,P＜0.05）;仔鼠各脑区的β微管蛋白Ⅲ型（Tuj）表达无明显改变;10.0 mg/kg组雄性仔鼠和各染毒组雌性仔鼠的海马及10.0 mg/kg组雌性仔鼠皮层生长相关蛋白43（GAP-43）表达升高,差异均有统计学意义（P＜0.05）,且有剂量相关性（雄性：r海马=0.882;雌性：r海马=0.997,r皮层=0.99,P＜0.05）;仔鼠各脑区的突触蛋白Ⅰ（Synapsin Ⅰ）表达无明显改变.10.0 mg/kg组雄性仔鼠海马、纹状体及雌性仔鼠皮层组织,各染毒组雌性仔鼠海马组织及1.0、10.0 mg/kg组纹状体组织突触后致密蛋白95（PSD95）表达降低,差异均有统计学意义（P＜0.05）,PSD95表达与染毒剂量呈依赖性下降（雄性：r海马=-0.991;雌性：r纹状体=-0.996,r皮层=-0.995,P＜0.05）.结论 出生后早期接触LCT,对仔鼠大脑突触蛋白的表达均有一定的影响;提示LCT可能影响仔鼠大脑突触联系的构建.

Objective To evaluate the influence on the synaptic protein expression in different brain regions of ICR mice after lambda-cyhalothrin （LCT） exposure during postnatal period. Methods Two male and 4 female healthy ICR mice were put in one cage. It was set as pregnancy if vaginal plug was founded.Offspring were divided into 5 groups randomly, and exposed to LCT （0.01% DMSO solution） at the doses of 0.1, 1.0 and 10.0 mg/kg by intragastric rout every other day from postnatal days （PND） 5 to PND13, control animals were treated with normal saline or DMSO by the same route. The brains were removed from pups on PND14, the synaptic protein expression levels in cortex, hippocampus and striatum were measured by western blot. Results GFAP levels of cortex and hippocampus in the LCT exposure group increased with doses, as compared with control group （P＜0.05）, while Tuj protein expression did not change significantly in the various brain regions of ICR mice. GAP-43 protein expression levels in the LCT exposed mouse hippocampus and in female ICR mouse cortex increased with doses. as compared with control group （P＜0.05）. Presynaptic protein （Synapsin Ⅰ） expression levels did not change obviously in various brain regions. However, postsynaptic density protein 95 （PSD95） expression levels of the hippocampus and striatum in male offspring of 10.0 mg/kg LCT group, of cortex of female LCT groups, and of female offspring in all exposure groups, of striatum, in 1.0 or 10.0 mg/kg LCT exposure groups significantly decreased （P＜0.05）. Conclusions Early postnatal exposure to LCT affects synaptic protein expression. These effects may ultimately affect the construction of synaptic connections.