壬基酚对雄性仔代学习记忆和海马超微结构的影响

目的 探讨母体壬基酚暴露对后代学习记忆的影响.方法 受试雌鼠与雄鼠同笼,见阴栓确定受孕后分组试验:将SD大鼠随机分为4组(对照组、50mg/kg、100mg/kg、200mg/kg壬基酚组),每组6～7只,妊娠第9～15天灌胃壬基酚.用Morris水迷宫和跳台的方法观察壬基酚对仔鼠学习记忆的影响;海马组织透射电镜观察其病理变化.结果 NP200mg/kg组仔鼠水迷宫中逃避潜伏期延长(61.14±5.92)s,错误次数增加(4.57±1.13)次;跳台实验中反应时间延长(37.5±6.3)s,步下潜伏期缩短(97.8±11.0)s,错误次数增加(3.0±1.4)次,阴性对照组分别为(35.85±4.29)s,(2.57±0.97)次,(27.1±3.8)s,(172.0±89.2)s,(0.9±0.7)次)],与对照组比较,差异具有显著性(P<0.05).NP200mg/kg剂量组仔鼠海马组织电镜下见线粒体肿胀呈空泡样变,染色质浓缩成块状聚集在核周围.结论 壬基酚官内暴露可导致仔鼠空间学习记忆障碍和海马超微结构改变.

Effects of nonylphenol exposure via placenta on spatial learning and memory capacity and uitrastructural changes in hippocampus of offspring in rat

Objective To explore the influence of nonylphenol(NP) on the filial generation rats spatial learning and memory capacity which were exposed to the parent rat during its pregnancy. Methods At the first day of the pregnancy, the rats were divided into four groups, which were orally administered with NP at doses of 0,50, 100 and 200 mg/kg,respectively, on gestational days 9～15. Cognitive function was tested by Morris water maze and step-down test. The ultrastructure of hippocampus tissues were observed by electronic microscope.Result The escape latency extended ((61.14±5.92) s) and erroring time increased ((4.57±1.13)times) in Morris water maze, and step down latency extended ((37.5±6.3)s), step through latency shortened((97.8±11.0)s) and erroring time increased ((3.0±1.4) times) in step down test in the N P 200 mg/kg treated groups (P<0 05). The correspond indexes were separately (35.85±4. 29) s, (2.57±0.97) time, (27.1±3.8) s,(172.0±89.2)s and(0.9±0.7)time in control group. Compared to the control group, there were significant differences in the results of the water maze test and step-down test between NP 200 mg/kg and the control group (P <005). The changes of the uhrastructure were found among the hippocampus neurons of NP 200 mg/kg group that characterized with chromatin condensed,clumped in circa-nuclei and mitochondrial tumefaction and vacuolization.Conclusion Exposures to NP during gestation might decreased abilities of spatial learning and memory capacity on F1 rats significantly.