Oshiro Wendy M, Krantz Q Todd, Bushnell Philip J
Neurotoxicology Division and Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, USA.
Neurotoxicol Teratol. 2008 May-Jun;30(3):167-74. doi: 10.1016/j.ntt.2008.01.002. Epub 2008 Jan 12.
The aliphatic hydrocarbon perchloroethylene (PCE) has been associated with neurobehavioral dysfunction including reduced attention in humans. The current study sought to assess the effects of inhaled PCE on sustained attention in rats performing a visual signal detection task (SDT). Due to its similarities in physiological effect to toluene and trichloroethylene (TCE), two other commonly used volatile organic compounds (VOCs) known to reduce attention in rats, we hypothesized (1) that acute inhalation of PCE (0, 500, 1000, 1500 ppm) would disrupt performance of the SDT in rats; (2) that impaired accuracy would result from changes in attention to the visual signal; and (3) that these acute effects would diminish upon repetition of exposure. PCE impaired performance of the sustained attention task as evidenced by reduced accuracy [P(correct): 500 to 1500 ppm], elevated response time [RT: 1000 and 1500 ppm] and reduced number of trials completed [1500 ppm]. These effects were concentration-related and either increased (RT and trial completions) or remained constant [P(correct)] across the 60-min test session. The PCE-induced reduction in accuracy was primarily due to an increase in false alarms, a pattern consistent with reduced attention to the signal. A repeat of the exposures resulted in smaller effects on these performance measures. Thus, like toluene and TCE, inhaled PCE acutely impaired sustained attention in rats, and its potency weakened upon repetition of the exposure.
脂肪族碳氢化合物全氯乙烯（PCE）与神经行为功能障碍有关，包括人类注意力下降。本研究旨在评估吸入PCE对执行视觉信号检测任务（SDT）的大鼠持续注意力的影响。由于其生理效应与甲苯和三氯乙烯（TCE）相似，这两种常用的挥发性有机化合物（VOCs）已知会降低大鼠的注意力，我们假设：（1）急性吸入PCE（0、500、1000、1500 ppm）会干扰大鼠的SDT表现；（2）准确性受损将源于对视觉信号注意力的改变；（3）重复暴露后这些急性效应会减弱。PCE损害了持续注意力任务的表现，表现为准确性降低[P（正确）：500至1500 ppm]、反应时间延长[RT：1000和1500 ppm]以及完成试验次数减少[1500 ppm]。这些效应与浓度相关，在60分钟的测试过程中，反应时间和试验完成次数增加，而准确性保持不变。PCE导致的准确性降低主要是由于误报增加，这一模式与对信号注意力的降低一致。重复暴露对这些表现指标的影响较小。因此，与甲苯和TCE一样，吸入PCE会急性损害大鼠的持续注意力，且重复暴露后其效力会减弱。
