Mitsushima D, Yamanoi C, Kimura F
Department of Physiology, Yokohama City University School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama 236-0004, Japan.
Brain Res. 1998 Sep 14;805(1-2):207-12. doi: 10.1016/s0006-8993(98)00735-5.
We examined the effects of the restriction of environmental space on hippocampal acetylcholine release and spontaneous locomotor activity. Four days after the housing in a large or small cage, sampling for microdialysis study was begun. The locomotor activity counts exhibited significant daily changes in all rats in either the large or small cage. But, the mean locomotor activity counts in rats in the small cage was significantly less than that in the large cage. In contrast, the amount of acetylcholine collected per 20-min sample exhibited significant diurnal changes in all six rats in the large cage and in 5 of 6 rats in the small cage. The mean acetylcholine release in the rat in the small cage was significantly lower than that in the rat in the large cage during the dark phase, but not during the light phase. In addition, during the dark phase, hippocampal acetylcholine release was closely associated with spontaneous activity in all six rats in the large cage but not in 3 of 6 rats in the small cage. The present study suggests that the restriction of environmental space somehow interfere with the spontaneous locomotor activity and hippocampal acetylcholine release during the dark phase.
我们研究了环境空间限制对海马乙酰胆碱释放和自发运动活动的影响。将大鼠饲养在大笼子或小笼子中四天后，开始进行微透析研究的采样。无论在大笼子还是小笼子中，所有大鼠的运动活动计数均呈现出显著的每日变化。但是，小笼子中大鼠的平均运动活动计数明显低于大笼子中的大鼠。相比之下，在大笼子中的所有六只大鼠以及小笼子中的六只大鼠中的五只中，每20分钟样本收集的乙酰胆碱量呈现出显著的昼夜变化。在黑暗阶段，小笼子中大鼠的平均乙酰胆碱释放量明显低于大笼子中大鼠的，但在光照阶段则不然。此外，在黑暗阶段，大笼子中的所有六只大鼠的海马乙酰胆碱释放与自发活动密切相关，但小笼子中的六只大鼠中有三只并非如此。本研究表明，环境空间的限制在某种程度上会干扰黑暗阶段的自发运动活动和海马乙酰胆碱释放。
