不同的光线强度对丰富环境下大鼠运动水平的影响

The effects of light intensity on the voluntary exercise level of rats in an enriched environment

目的探讨不同的光线强度对丰富环境和空旷环境下大鼠运动水平的影响，以及运动水平的改变对丰富环境效果的影响。方法将30只雄性SD大鼠分别放置于强光加丰富环境，弱光加丰富环境，强光加空旷环境和弱光加空旷环境中，对4种不同实验环境中大鼠的运动轨迹进行监控，并用Etho Vision XT 7．0版动物轨迹分析系统记录和比较每只大鼠在1h观测时间内的路程、速度、活动时间、活动频率、移动时间、移动频率等6个运动指标的变化。结果在强光环境下，除速度外，大鼠在丰富环境干预下其余5项运动指标均明显高于空旷环境时的运动水平（P〈0．05）；同样，弱光环境下，大鼠在丰富环境干预时的5项运动指标（除速度外）均高于空旷环境（尸〈0．05）。弱光加丰富环境大鼠的运动强度（平均速度、活动频率、位移频率）均高于强光加丰富环境大鼠（P（0．05）；弱光加空旷环境下大鼠的运动强度（平均速度、活动频率、位移频率）高于强光加空旷环境大鼠（P〈0．05）；弱光加丰富环境大鼠的运动持久度（总路程、活动时间、移动时间）高于强光加丰富环境大鼠（P〈0．05）；弱光加空旷环境下大鼠的运动持久度（总路程、活动时间、移动时间）均高于强光加空旷环境大鼠（P〈0．05）。结论丰富环境和光强均是大鼠自主运动的2个独立影响因素，可以共同对大鼠的运动水平产生作用。

Objective To study the effects of light at different intensities and an enriched environment （EE） on rats＇ level of voluntary exercise, and to explore the resulting benefits. Methods Thirty male Sprague- Dawley rats were tested successively under 4 different experimental conditions： EE ＋ strong light, EE ＋ dim light, open-field environment （OFE） ＋ strong light and OFE ＋ dim light. Each rat＇s path in the different conditions was recorded using an automated tracking system. Distance moved （m）, velocity （m/s） , mobile duration （s）, mobile frequency, moving duration （s） and moving frequency were recorded over a one-hour period. Results The EE rats were significantly more active than the OFE rats in both strong and dim light. All rats were more mobile under dim light than under strong light. Conclusion Environment and light intensity are independent factors affecting rats＇ voluntary exercise levels, and they can exert their influence in synergy.