Department of Public Health, University of Szeged, H-6720 Szeged, Dóm tér 10, Hungary.
Environ Toxicol Pharmacol. 2005 May;19(3):785-96. doi: 10.1016/j.etap.2004.12.045.
Young adult male Wistar rats (24/group) were treated for 5 weeks with methyl mercury(II)chloride (corresponding to 0.5 and 2.0mgHg°/kg b.w., control: distilled water) by gavage, followed by a 19 weeks post-treatment period. Spontaneous motility, psychomotor performance and sensorimotor gating was repeatedly tested, electrophysiological recordings done, in the rats throughout the whole experiment. Decreased horizontal open field activity, reduced number of "noise positive" startle responses, as well as increase of startle response onset latency and peak time, and decrease of peak amplitude, was seen in the treated animals. Most changes disappeared in the post-treatment period. In the spontaneous cortical and hippocampal activity, altered distribution of the frequency bands was seen after 5 weeks of treatment but not at the end of the post-treatment period. Hippocampal population spikes in the treated animals were depressed and showed less potentiation, which effect was still present 19 weeks after finishing the treatment. The duration of the sensory cortical evoked potentials was shorter than in the controls. In the treated rats, tyrosine hydroxylase-immunoreactive boutons in the substantia nigra pars reticulata were shrunk; blood and brain Hg levels were significantly higher and decreased only slowly. Considering the continuous presence of low levels of mercurials in the human environment, effects of this kind may be supposed as the background of some human neurobehavioral abnormalities.
雄性 Wistar 大鼠（每组 24 只）被给予甲基汞（II）氯化物（相当于 0.5 和 2.0mgHg°/kg bw，对照组：蒸馏水）灌胃，持续 5 周，然后进行 19 周的治疗后阶段。在整个实验过程中，反复测试大鼠的自发运动、精神运动表现和感觉运动门控，进行电生理记录。在治疗动物中，观察到水平开放场活动减少，“噪声阳性”惊跳反应数量减少，惊跳反应起始潜伏期和峰值时间增加，峰值幅度降低。大多数变化在治疗后消失。在自发皮质和海马活动中，在治疗 5 周后观察到频带分布的改变，但在治疗后结束时没有观察到。治疗动物的海马群体峰电位受到抑制，表现出较弱的增强作用，这种作用在治疗结束后 19 周仍存在。感觉皮质诱发电位的持续时间短于对照组。在治疗大鼠中，黑质网状部酪氨酸羟化酶免疫反应性末梢缩小；血液和大脑中的 Hg 水平显著升高，且下降缓慢。考虑到低水平的汞化合物在人类环境中持续存在，这种影响可能被认为是一些人类神经行为异常的背景。
