Response inhibition is impaired by developmental methylmercury exposure: acquisition of low-rate lever-pressing.
Response inhibition is impaired by developmental methylmercury exposure: acquisition of low-rate lever-pressing.
复制标题
发育过程中接触甲基汞会损害反应抑制：低速率杠杆按压的获得。
DOI：
10.1016/j.bbr.2013.05.038
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发表时间：
2013
影响因子：
2.7
通讯作者：
Donlin,WendyD
中科院分区：
文献类型：
--
作者：
Newland,MChristopher;Hoffman,DanielJ;Heath,JohnC;Donlin,WendyD
发育甲基汞（甲基汞）暴露产生的歧视逆转程序的反应perseveration，破坏敏感性的强化，并提高敏感性多巴胺激动剂-一个配置文件表明在行为抑制的赤字。为了检查抑制，我们研究了甲基汞的影响收购和持久性的低利率按下历史的高利率响应。此外，我们还研究了长期暴露于硒是否能防止甲基汞的发育神经毒性。雌性大鼠通过母体暴露于含0 ppm、0.5 ppm或5 ppm甲基汞的饮用水中，产生约0 μg/kg/天、40 μg/kg/天或400 μg/kg/天的汞。母鼠（妊娠期）和子代（终生）食用含0.06ppm或0.6ppm硒（以亚硒酸钠计）的纯化饲料，形成2（终生饲料）× 3（发育期甲基汞）析因设计。成年后代的两个时间表下的强化压力。差异强化高速率（DRH）时间表规定了严格的反应要求，在整个研究中保持不变。一个高利率百分位数的时间表（PCNT-H）纳入了一个灵活的标准，加强短interresponse时间使用的调整标准，最近的表现是敏感的。高频率反应稳定后，PCNT-H时间表突然逆转，加强长的相互反应时间。由于高速率反应爆发的侵入，在甲基汞暴露的大鼠中，低速率反应的获得受损。DRH反应率没有变化。膳食硒不影响甲基汞的作用。高利率的操作性行为持续，这表明，妊娠期甲基汞暴露损害反应抑制-效果，延长以前报告的结果使用选择程序或空间和视觉歧视逆转。
Developmental methylmercury (MeHg) exposure produces response perseveration on discrimination reversal procedures, disrupts sensitivity to reinforcement, and enhances sensitivity to dopamine agonists – a profile suggesting a deficit in behavioral inhibition. To examine inhibition, we examined MeHg's effects on the acquisition and persistence of low-rate lever-pressing following a history of high-rate responding. Additionally, we examined whether chronic exposure to selenium protects against MeHg's developmental neurotoxicity. Female rats were exposedin uterovia maternal exposure to drinking water containing 0 ppm, 0.5 ppm or 5 ppm of Hg as MeHg, producing approximately 0 μg/kg/day, 40 μg/kg/day, or 400 μg/kg/day of Hg. The mothers (during gestation) and the offspring (throughout life) consumed a purified diet containing 0.06 ppm or 0.6 ppm of Se (as sodium selenite), forming a 2 (lifespan diet) × 3 (developmental MeHg) factorial design. Adult offspring lever-pressed under two schedules of reinforcement. A differential reinforcement of high-rate (DRH) schedule imposed rigid response requirements that remained constant through the study. A high-rate percentile schedule (PCNT-H) incorporated a flexible criterion that reinforced short interresponse times using an adjusting criterion that was sensitive to recent performance. After high-rate responding stabilized, the PCNT-H schedule was abruptly inverted by reinforcing long interresponse times. Acquisition of low-rate responding was impaired in the MeHg-exposed rats because of intrusions of high-rate response bursts. DRH response rates did not change. Dietary selenium did not influence MeHg's effects. High-rate operant behavior perseverated, suggesting that gestational MeHg exposure impairs response inhibition – an effect that extends results previously reported using choice procedures or spatial and visual discrimination reversals.