Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710 USA; Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710 USA.
Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710 USA; Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27710 USA.
Toxicology. 2020 Jan 15;429:152327. doi: 10.1016/j.tox.2019.152327. Epub 2019 Nov 5.
Diazinon is a widely-used organophosphate pesticide. Pulsatile exposure to diazinon during neonatal development has previously been shown cause long-term neurobehavioral impairments in rats. However, the effects of chronic low concentration exposures during perinatal development remain unclear. This experiment evaluated such effects in Sprague-Dawley rats by implanting osmotic pumps in breeder females prior to conception (N = 13-15 litters per condition) which then delivered chronic, zero order kinetic low-level infusions of 0, 114 or 228 ug/day of diazinon throughout pregnancy. One male and one female from each litter was assessed with a battery of behavioral tests that continued from four weeks of age into adulthood. Litter was used as the unit of variance for the analysis of variance test of significance, with sex as a within litter factor. Diazinon treatment condition was the between subjects factor and time or sessions were repeated measures. Chronic diazinon exposure from pre-mating until the neonatal period caused a significant (p < 0.05) increase in percent of time spent on the open arms of the elevated plus maze, an index of risk-taking behavior. Gestational and lactational diazinon exposure also caused a significant (p < 0.05) degree of hyperactivity in the Figure-8 apparatus during adolescence, specifically affecting the early part of the hour-long test session. This effect had dissipated by the time the rats reached adulthood. Diazinon exposure also caused a significant impairment in novel object recognition, a test of cognitive function. Offspring exposed to 228 ug/day diazinon (p < 0.05) showed significantly less preference for the novel vs. familiar object than controls during the first five minutes of the novel object recognition test.
敌敌畏是一种广泛使用的有机磷农药。先前的研究表明，在新生儿发育过程中脉冲式接触敌敌畏会导致大鼠长期神经行为损伤。然而，围产期慢性低浓度暴露的影响尚不清楚。本实验通过在受孕前向繁殖雌性大鼠植入渗透泵（每个条件下有 13-15 个窝），以评估这种影响，该渗透泵持续在整个怀孕期间以零级动力学输送低水平的慢性敌敌畏零级恒速输注，剂量分别为 0、114 或 228ug/天。每个窝中各有一只雄性和一只雌性大鼠接受一系列行为测试，从四周龄持续到成年期。使用窝作为方差分析的单位进行显著性方差分析，性别作为窝内因素。敌敌畏处理条件是被试间因素，时间或测试次数是重复测量因素。从交配前到新生儿期的慢性敌敌畏暴露会导致高架十字迷宫开放臂上的时间百分比显著增加（p<0.05），这是冒险行为的一个指标。妊娠期和哺乳期敌敌畏暴露也会导致青春期时在“8 字形”仪器中出现明显的多动（p<0.05），特别是在长达一小时的测试过程的早期部分。当大鼠进入成年期时，这种影响已经消散。敌敌畏暴露还会导致新颖物体识别测试中的认知功能显著受损。接触 228ug/天敌敌畏的后代（p<0.05）在新颖物体识别测试的前五分钟内，与对照组相比，对新颖物体的偏好明显降低。
