Watanabe C, Suzuki T, Matsuo N
Department of Environmental Health Sciences, Tohoku University School of Medicine, Sendai, Japan.
Toxicology. 1990 Dec 3;64(3):245-53. doi: 10.1016/0300-483x(90)90117-y.
The effect of a brief exposure to heat/cold on the subsequent development of toxicity of sodium selenite (SS) was evaluated in male ICR mice. Mice were exposed to one of three ambient temperatures (Ta; approx. 8 degrees, 22 degrees and 33 degrees C). One and a half hours after the beginning of the exposure, they were injected with 45 mumol/kg of SS subcutaneously. The exposure was terminated 3 h after injection and the mice were returned to Ta of 22 degrees C. Heat-induced enhancement of toxicity was recognized in some plasma enzyme activities 3 days after injection and in the suppression of body weight for up to 3 weeks. On the other hand, cold exposure alleviated SS toxicity in terms of these indices. Thus, the Ta during this short period was recognized to be important in determining subsequent development of SS toxicity. At the end of the thermal exposure, heat increased renal concentration of the injected Se. On the other hand, in the liver and the other organs examined, the highest Se concentration was found in the cold-exposed group, followed by the control (room temperature) and the heat-exposed. The relation between the modification of toxicity and the altered distribution was not clear. Neither glutathione level in the liver nor that in the kidney at the time of SS injection could explain the observed modification of the toxicity.
在雄性ICR小鼠中评估了短期热/冷暴露对亚硒酸钠（SS）后续毒性发展的影响。将小鼠暴露于三种环境温度（Ta；约8℃、22℃和33℃）之一。暴露开始后1.5小时，给它们皮下注射45μmol/kg的SS。注射后3小时终止暴露，将小鼠放回22℃的Ta环境。注射后3天，在一些血浆酶活性方面以及长达3周的体重抑制方面，均观察到热诱导的毒性增强。另一方面，就这些指标而言，冷暴露减轻了SS毒性。因此，在这段短时间内的Ta被认为对确定SS毒性的后续发展很重要。在热暴露结束时，热增加了注射的硒在肾脏中的浓度。另一方面，在肝脏和其他检查的器官中，冷暴露组的硒浓度最高，其次是对照组（室温）和热暴露组。毒性改变与分布变化之间的关系尚不清楚。SS注射时肝脏和肾脏中的谷胱甘肽水平均无法解释所观察到的毒性改变。
